Science fairs are a great chance for 7th graders to explore the world, practice the scientific method, and show off neat, testable results.
Below you’ll find a readable introduction that explains how to pick and run a successful project, safety and presentation tips, and then 150 science fair project ideas for 7th grade grouped by topic.
Each idea includes an objective, the basic materials you’ll need, a short method, and what you’ll learn. The descriptions are written so you can copy-paste them directly into a project notebook or report.
Must Read: 120 Absolute New Biology Project Topics For Class 10
How to use these science fair project ideas for 7th grade
- Pick a topic you’re curious about. If you love plants, animals, chemistry, electronics, or food — choose something that keeps you excited. Curiosity makes the work easier and more fun.
- Keep it testable. A great science fair project asks a clear question you can test with experiments. Example: “How does the amount of sunlight affect tomato plant height?” is testable. “Why do plants need sunlight?” is too broad.
- Follow the scientific method.
- Ask a clear question.
- Do background research.
- Form a hypothesis (an educated guess).
- Plan and run experiments (control variables carefully).
- Record and analyze results.
- Draw a conclusion.
- Share your findings with a display board and short report.
- Think about variables.
- Independent variable: what you change (e.g., light hours).
- Dependent variable: what you measure (e.g., plant height).
- Controlled variables: things you keep the same (same soil, same water amount).
- Be realistic about time and materials. Some projects take days, others need weeks. Choose projects you can finish in the time given and with materials you can get.
- Safety first. Wear safety goggles when needed, follow teacher guidance on chemicals and heat sources, never conduct risky experiments alone, and ask permission before using tools or live animals.
- Document everything. Keep a lab notebook with dates, steps, measurements, and photos. Judges love clear records.
- Presentation matters. Use graphs, clean photos, and simple charts on your display board. Practice a 1-2 minute summary of your project and a 30-second elevator pitch.
Safety & ethical reminders for 7th grade projects
- Ask your teacher or parent before starting experiments that use heat, flames, chemicals, live animals, or electricity.
- If your project uses living creatures, follow humane guidelines and get approval. Don’t harm animals.
- Label any hazardous materials clearly and dispose of them safely.
- Keep an adult present for experiments involving tools, heat, or batteries.
- When in doubt, choose a safer variant of your idea (e.g., simulations or models instead of live animals).
What to include on your science fair display and report
- Title (clear and short) — include the question.
- Question and hypothesis.
- Materials list.
- Procedure (step by step).
- Data (tables, photos).
- Graphs and analysis.
- Conclusion and explanation of whether the hypothesis was supported.
- Sources and acknowledgements.
- Optional: ideas for further study.
150 Science Fair Project Ideas for 7th Grade
Biology & Life Science (20 ideas)
- Effect of Light Angle on Plant Growth
Objective: Test how light direction affects seedling growth.
Materials: potted seedlings, lamp, ruler.
Method: Place plants with light from different angles; measure growth weekly.
Learn: Phototropism and plant hormones. - Which Soil Type Holds Water Best?
Objective: Compare water retention of sand, clay, and potting soil.
Materials: soil samples, cups, water, timer.
Method: Add equal water, measure drainage/remaining moisture over time.
Learn: Soil porosity and plant watering needs. - Yeast Respiration: Sugar Type Effects
Objective: See which sugar causes the most CO₂ from yeast.
Materials: yeast, glucose, sucrose, fructose, balloons, bottles.
Method: Mix yeast and different sugars, capture gas in balloons and compare sizes.
Learn: Fermentation and energy sources. - Ant Behavior and Food Types
Objective: Test which foods attract ants fastest.
Materials: sugar, protein (peanut butter), oil, paper.
Method: Place food spots and time ant arrival and number.
Learn: Foraging behavior and preferences. - Do Plants “Remember” Watering Schedules?
Objective: Compare plants watered regularly vs. randomly.
Materials: identical plants, water schedule, ruler.
Method: Water two groups differently, measure health and growth.
Learn: Plant stress and growth patterns. - Effect of Acid Rain on Seed Germination
Objective: Test how acidic water affects seed sprouting.
Materials: vinegar solution dilutions, seeds, trays.
Method: Water seeds with different pH levels and track germination rate.
Learn: Environmental impact on plants. - Natural Antibiotics from Common Herbs
Objective: Test if garlic or onion extract slows bacterial growth (use safe, non-pathogenic cultures or simulated tests).
Materials: garlic, onion, agar plates (or alternatives), petri dishes (teacher supervised).
Method: Apply extracts to cultures and measure zones of inhibition.
Learn: Antimicrobial properties and lab safety. - How Does Temperature Affect Heart Rate (Human)
Objective: See how body temperature changes heart rate during rest/after activity.
Materials: thermometer, stopwatch, volunteers (consent), activity plan.
Method: Measure resting heart rate and after mild exercise at different room temps.
Learn: Physiology of heart rate. - Effect of Salt on Plant Growth
Objective: Test how saline water affects seedlings.
Materials: salt solutions, plants, watering schedule.
Method: Water plants with increasing salt concentrations and observe health.
Learn: Soil salinity effects. - Bread Mold Growth Under Different Conditions
Objective: Compare mold growth in moist vs dry, hot vs cool.
Materials: bread slices, zip bags, dampness control.
Method: Store bread under varied conditions; photograph daily.
Learn: Fungi growth and hygiene. - Does Music Affect Plant Growth?
Objective: Test growth of plants exposed to different music genres.
Materials: plants, speakers, playlists.
Method: Play different music and compare growth after weeks.
Learn: Stimulus effects and experimental controls. - Comparing Biodegradation Rates of Materials
Objective: Test how fast paper, plastic, and cloth break down in soil.
Materials: material pieces, soil, labeled bags.
Method: Bury items for set time and check degradation.
Learn: Environmental decomposition. - How Salt Affects Brine Shrimp Survival
Objective: Check survival rate of brine shrimp at different salt concentrations.
Materials: brine shrimp eggs, saltwater setups, microscopes.
Method: Prepare salinity gradients and track hatching/survival.
Learn: Osmoregulation and habitats. - Comparing Handwashing Methods’ Effectiveness
Objective: Test which washing method removes the most microbes (use safe agar plates with supervision) or simulated glitter method.
Materials: glitter or agar plates, soap types.
Method: Compare before/after counts or glitter removal.
Learn: Hygiene and germ transmission. - Do Plants Grow Faster with Homemade Fertilizer?
Objective: Test kitchen compost vs. commercial fertilizer vs. none.
Materials: fertilizers, plants, measuring tools.
Method: Apply different fertilizers and compare growth.
Learn: Nutrients and plant care. - How Does Air Pollution Affect Lichen Growth (or Model Lichens)?
Objective: Compare lichen presence near busy roads vs quiet areas (or simulate).
Materials: field survey tools or model substrates.
Method: Count lichens or use simulation to model pollutant effects.
Learn: Bioindicators and air quality. - Effect of Different Drinks on Tooth Enamel (Model Tooth Experiment)
Objective: Test erosion of egg shell (model for enamel) in soda, water, juice.
Materials: eggshells, drinks, containers.
Method: Soak shells and observe color, hardness changes.
Learn: Acid erosion and dental health. - How DO Light Colors Affect Insect Attraction?
Objective: Test whether certain colors attract more insects.
Materials: colored paper, sticky traps.
Method: Place traps of different colors and count insects caught.
Learn: Insect vision and ecology. - Plant Transpiration Rates in Different Humidities
Objective: Measure how much water leaves a leaf in varied humidity.
Materials: balance, leaves, humidity control (humidifier/room).
Method: Weigh leaves over time in different humidity conditions.
Learn: Transpiration and plant water loss. - Comparing Decomposition: Shredded vs Whole Leaves
Objective: See which decomposes faster in a compost bin.
Materials: leaves, bin, timer.
Method: Mix samples, check mass or breakdown over weeks.
Learn: Surface area effects on decomposition.
Chemistry (20 ideas)
- Which Antacid Works Best? (Neutralization Test)
Objective: Test neutralizing power of different antacids.
Materials: antacids, acid solution (vinegar dilute), pH strips.
Method: Add antacid until pH returns to neutral; compare amounts.
Learn: Acid-base reactions and pH. - Effect of Temperature on Reaction Rate (Baking Soda + Vinegar)
Objective: Measure how temp affects reaction speed.
Materials: baking soda, vinegar, thermometer, stopwatch.
Method: Run reaction at different temperatures and time fizzing.
Learn: Collision theory and kinetics. - How Do Different Liquids Conduct Electricity?
Objective: Test conductivity of tap water, saltwater, sugar water.
Materials: simple circuit, electrodes, voltmeter.
Method: Measure current through each liquid.
Learn: Ions and conductivity. - Creating Natural pH Indicators from Red Cabbage
Objective: Make a pH indicator and test household substances.
Materials: red cabbage, blender, pH solutions.
Method: Make extract and drop on samples to compare color changes.
Learn: Acids, bases, and indicator chemistry. - Effect of Surface Area on Rate of Dissolving
Objective: Test how crushed vs whole tablets dissolve.
Materials: tablets, water, stopwatch, beakers.
Method: Measure dissolve time for different sizes.
Learn: Surface area and reaction rates. - Which Material Best Insulates Heat?
Objective: Test heat retention in foam, metal, glass containers.
Materials: containers, hot water, thermometer.
Method: Measure temp drop over time.
Learn: Thermal conductivity. - Making and Testing Biodegradable Plastics
Objective: Create plastics from starch and test strength.
Materials: cornstarch, glycerin, baking soda, molds.
Method: Make samples and test flexibility and water resistance.
Learn: Polymers, biodegradation, materials science. - Does Temperature Affect Solubility of Salt?
Objective: Compare salt solubility at different temps.
Materials: salt, water, hotplate, beakers.
Method: Add salt until saturation; measure amount dissolved.
Learn: Solubility and saturation. - Rust Formation: Effect of Saltwater vs Freshwater
Objective: Test corrosion speed in different solutions.
Materials: iron nails, saltwater, freshwater, oil control.
Method: Submerge nails and observe rusting over days.
Learn: Oxidation and corrosion. - Compare the pH of Different Soaps and Detergents
Objective: Measure and compare pH values.
Materials: pH strips, soap solutions.
Method: Dissolve soaps and test pH.
Learn: Basicity and cleaning chemistry. - Electrolysis of Water: Gas Collection
Objective: Split water into hydrogen and oxygen with safe setup (teacher supervised).
Materials: battery, electrodes, water with salt, tubes.
Method: Run low-voltage electrolysis and capture gas.
Learn: Water composition and electrochemistry. - Effect of Catalysts: Hydrogen Peroxide & Yeast
Objective: Test how yeast speeds up H₂O₂ breakdown.
Materials: H₂O₂, yeast, measuring cup.
Method: Mix and measure bubble rate vs no catalyst.
Learn: Catalysts and reaction rates. - Does Color of Light Change Photosensitive Reactions?
Objective: Test photochemical reaction rates under different colors.
Materials: light filters, photosensitive paper or dye.
Method: Expose and compare reaction or color change.
Learn: Light wavelength effects. - Testing Vitamin C Levels in Fruit Juices
Objective: Compare vitamin C content using iodine titration (simple, supervised method).
Materials: iodine solution, starch indicator, juices.
Method: Titrate to endpoint and compare volumes used.
Learn: Titration basics and nutrient comparison. - Which Household Item Neutralizes Odors?
Objective: Test baking soda, vinegar, activated charcoal.
Materials: odor source, test containers, smells observation log.
Method: Place items with odor and note smell after set time.
Learn: Adsorption and neutralization. - Comparing Concentration Using Paper Chromatography
Objective: Separate ink components from different markers.
Materials: filter paper, markers, solvent.
Method: Run chromatography and measure spread.
Learn: Molecule polarity and separation methods. - Does Temperature Affect Density of Liquids?
Objective: Measure density change of water at different temps.
Materials: graduated cylinder, scale, water bath.
Method: Weigh fixed volume of water at temps and calculate density.
Learn: Density and thermal expansion. - Making Superabsorbent Polymers from Diapers (safe demo)
Objective: Show water absorption of polymer crystals.
Materials: disposable diaper crystals (extracted), water.
Method: Measure grams of water absorbed per gram polymer.
Learn: Polymers and absorbency. - Comparing Food Preservatives’ Effectiveness
Objective: Test how different preservatives (salt, sugar, vinegar) prevent mold.
Materials: fruit slices treated with preservatives, observation.
Method: Store slices and check spoilage rate.
Learn: Preservation methods. - Saponification: Make Soap and Test Hardness
Objective: Create small batches of soap and compare cure/hardness.
Materials: oils, lye (supervised), molds.
Method: Make soap safely with supervision, test hardness after curing.
Learn: Organic chemistry basics (saponification).
Physics (20 ideas)
- Which Surface Produces the Most Friction?
Objective: Measure friction forces on different surfaces.
Materials: block, spring scale, wood, tile, carpet.
Method: Pull block across surfaces and record force.
Learn: Friction and surface interactions. - How Does Length of a Pendulum Affect Period?
Objective: Test pendulum period vs length.
Materials: string, weight, stopwatch.
Method: Make pendulums of different lengths and time swings.
Learn: Period, gravity, and pendulum math. - Investigate Buoyancy: Shape vs Volume
Objective: Test how shape affects floating with same material.
Materials: clay, water tub.
Method: Mold shapes and test whether they float and how they displace water.
Learn: Archimedes’ principle. - Which Material Makes the Best Sound Insulator?
Objective: Compare sound reduction by foam, fabric, cardboard.
Materials: sound source, decibel meter (or app), test panels.
Method: Measure sound levels behind different materials.
Learn: Sound insulation and wave absorption. - Build a Simple Electromagnet: Coil Turns vs Strength
Objective: See how coil turns affect lifting power.
Materials: iron nail, wire, battery, paper clips.
Method: Wrap different turns; test how many clips it picks up.
Learn: Electromagnetism and variables. - Solar Oven Efficiency with Different Reflectors
Objective: Test which material reflects heat best.
Materials: box, foil, mirror, black pot.
Method: Build ovens with different reflectors and measure temp increase.
Learn: Solar energy and thermal capture. - Ball Bounce: How Surface and Drop Height Affect Bounce
Objective: Measure bounce height on various surfaces and heights.
Materials: balls, meter stick, surfaces.
Method: Drop ball, measure rebound height.
Learn: Elasticity and energy transfer. - Does Temperature Affect Air Pressure Reading?
Objective: Compare pressure inside sealed bottles at different temps.
Materials: sealed bottles, thermometer, scale or gauge.
Method: Heat/cool bottles and note deformations or pressure proxies.
Learn: Gas laws. - Build a Water Rocket and Test Launch Angles
Objective: Determine best angle for maximum distance.
Materials: plastic bottle rocket, launcher, water.
Method: Launch at angles and measure distance.
Learn: Projectile motion and thrust basics. - How Does Weight Distribution Affect Roller Coaster Speed?
Objective: Model a coaster and test different weight placements.
Materials: toy car, track, weights, timer.
Method: Run car with various weight placements and time runs.
Learn: Center of mass and dynamics. - Investigate Insulation: Which Material Keeps Ice from Melting Fastest?
Objective: Test insulating effectiveness.
Materials: ice cubes, containers, different insulators.
Method: Measure melting time.
Learn: Heat transfer and insulation. - Comparing Reflectivity: How Color Affects Heat Absorption
Objective: See whether dark or light surfaces heat faster in sunlight.
Materials: black and white paper, thermometer.
Method: Place in sun and record temperature rise.
Learn: Absorption and albedo. - Magnetic Levitation Model Using Repelling Magnets
Objective: Build a simple levitation setup and test stability.
Materials: strong magnets, stands.
Method: Arrange magnets and measure levitation height and stability.
Learn: Magnetic forces and stability. - How Does Rope Thickness Affect Strength?
Objective: Test breaking strength of ropes of different thickness.
Materials: ropes, weights, hook.
Method: Apply weight until break and record max load.
Learn: Tensile strength and safety factor. - Measuring Reaction Time Under Different Conditions
Objective: Test reaction time when tired vs rested.
Materials: ruler drop test, volunteers.
Method: Perform reaction tests and compare averages.
Learn: Neuroscience basics. - Build a Simple Motor and Test Coil Size
Objective: Test motor speed with different coil sizes.
Materials: battery, magnets, wire, axles.
Method: Build motors and measure RPM (approx).
Learn: Electromagnetism and motors. - How Do Sound Frequencies Travel Through Different Materials?
Objective: Test which materials transmit sound best.
Materials: speaker, tubes of wood/plastic/metal, microphone.
Method: Measure sound at receiver end.
Learn: Sound transmission and mediums. - Investigate Heat Conduction in Metals vs Wood
Objective: Compare temperature change across different rods.
Materials: metal and wooden rods, heat source, thermometer.
Method: Heat one end and measure temperature along length.
Learn: Thermal conductivity. - Does Surface Area Affect Rate of Evaporation?
Objective: Test evaporation from flat vs deep containers.
Materials: water, containers, scale.
Method: Measure water loss over time.
Learn: Surface area and evaporation. - Testing Parachute Designs for Descent Speed
Objective: Find which parachute shape slows descent best.
Materials: fabric, strings, small weight, timer.
Method: Drop from height and time descent.
Learn: Air resistance and drag.
Environmental Science & Earth (15 ideas)
- Measuring Local Water pH and Pollution Levels
Objective: Test pH and simple pollutants at different sites.
Materials: pH strips, water sample jars, turbidity tube.
Method: Collect samples from sites and compare readings.
Learn: Water quality and human impact. - Does Composting Speed Depend on Aeration?
Objective: Compare compost piles turned regularly vs not turned.
Materials: compost bins, kitchen scraps, thermometer.
Method: Track temperature and decomposition speed.
Learn: Aerobic decomposition. - How Does Temperature Affect Soil Microbe Activity?
Objective: Measure decomposition rate at varied soil temps.
Materials: soil samples, organic matter, incubator options.
Method: Monitor CO₂ or mass loss.
Learn: Microbial activity and temp effects. - Pollinator Count: Which Flowers Attract More Bees?
Objective: Survey bees visiting different flower species.
Materials: field notebook, timers, camera.
Method: Count visits during set intervals.
Learn: Ecology and pollination. - Compare Runoff from Different Ground Covers
Objective: Test water runoff from grass, asphalt, mulch.
Materials: trays with surfaces, water, measuring cup.
Method: Simulate rain and measure runoff volume.
Learn: Permeability and urban runoff. - Microplastics: Which Household Items Shed Most Fibers?
Objective: Test fiber release from different fabrics.
Materials: wash tests with sieves, filters.
Method: Wash samples and filter wash water to estimate fibers.
Learn: Microplastic sources and environmental impact. - Does Urban Heat Island Effect Show in Your Town?
Objective: Compare temps in urban vs rural spots.
Materials: thermometer, map, data log.
Method: Measure temps at different locations and times.
Learn: Urban heat and land use. - Green Roof vs Regular Roof: Temperature Differences
Objective: Model green roof insulation on small boxes.
Materials: boxes, soil/plant cover, thermometers.
Method: Measure internal temps under sun.
Learn: Benefits of green roofs. - Which Mulch Conserves Soil Moisture Best?
Objective: Compare moisture under wood chips, straw, plastic.
Materials: pots, mulches, moisture meter.
Method: Water pots and measure moisture retention over time.
Learn: Mulch benefits for gardening. - Do Crushed Shells Affect Soil pH for Garden Plants?
Objective: Test effect of crushed shells on soil pH and plant growth.
Materials: shells, soil, pH strips, plants.
Method: Mix shells into soil and grow plants, measure pH and growth.
Learn: Soil amendments and pH buffering. - How Much CO₂ Do Houseplants Remove? (Model Estimate)
Objective: Estimate CO₂ uptake of common houseplants.
Materials: plant, sealed container, CO₂ sensor (or model calculations).
Method: Measure CO₂ change or calculate based on leaf area.
Learn: Plant photosynthesis and indoor air quality. - Testing Effectiveness of Different Water Filters
Objective: Compare sediment, charcoal, and store filters.
Materials: dirty water, filters, turbidity tests.
Method: Filter and compare clarity and odor.
Learn: Filtration methods. - Comparing Solar Panel Output in Different Angles
Objective: Test power output at various tilt angles.
Materials: small solar panels, multimeter, protractor.
Method: Measure voltage/current at different angles.
Learn: Solar energy optimization. - How Do Road Salt Runoff Levels Change After Snow Melt?
Objective: Measure chloride levels before and after melt (if seasonal).
Materials: water samples, chloride test strips.
Method: Collect runoff samples and compare.
Learn: Winter road salt environmental effects. - Investigate Local Noise Pollution Levels
Objective: Measure decibel levels around school vs busy street.
Materials: decibel meter (or phone app), map.
Method: Measure at set times and compare.
Learn: Noise pollution and impact on health.
Engineering & Robotics (15 ideas)
- Design a Bridge from Popsicle Sticks: Which Design Holds Most Weight?
Objective: Test truss designs for strength.
Materials: popsicle sticks, glue, weights.
Method: Build different bridge designs and load until failure.
Learn: Engineering design, stress distribution. - Build a Water Wheel and Measure Power Output
Objective: Test blade shapes for efficiency.
Materials: small wheel, water flow source, generator or dynamo.
Method: Measure rotation speed or light bulb brightness.
Learn: Renewable energy and mechanical advantage. - Which Paper Airplane Design Flies Farthest?
Objective: Compare DFA (design) for distance and stability.
Materials: paper, measuring tape, windless area.
Method: Fold different designs and measure distance.
Learn: Aerodynamics and design testing. - DIY Wind Turbine Blade Angle vs Power
Objective: Test blade pitch effect on power generation.
Materials: small turbine kit, fan, multimeter.
Method: Change blade angles and measure output.
Learn: Wind energy and blade design. - Robotic Arm: Grip Strength vs Motor Torque
Objective: Build a simple arm and test load it can lift.
Materials: servo motors, cardboard or kit parts, microcontroller.
Method: Incrementally add weights and find max lift.
Learn: Robotics basics and torque. - Insulated House Model: Best Design for Temperature Control
Objective: Compare insulation layouts and window designs.
Materials: model houses, insulation materials, heat lamp.
Method: Heat models and measure interior temp over time.
Learn: Energy efficiency and insulation. - Test Different Wheel Types on Traction
Objective: Compare traction of rubber vs plastic wheels on surfaces.
Materials: model car, different wheels, incline plane.
Method: Measure distance or climb angle achievable.
Learn: Traction and surface interaction. - Design a Simple Water Purifier and Test Clarity
Objective: Build filter columns and compare water clarity.
Materials: sand, gravel, charcoal, bottles.
Method: Filter dirty water and measure turbidity.
Learn: Filtration and design iteration. - Elevator Model: Counterweight vs Motor Power Efficiency
Objective: Test which method uses less energy for lifting loads.
Materials: string, weights, small motor, battery.
Method: Compare current draw for lifting same load with counterweight vs pure motor.
Learn: Mechanical advantage and energy. - Study Drone Propeller Pitch vs Lift (simulated or kit)
Objective: Test lift with varied propeller pitch.
Materials: drone kit or small motors, props, scale.
Method: Measure thrust produced by different props.
Learn: Aeronautical design. - Test Different Adhesives for Strength and Flexibility
Objective: Compare glue types for bond strength.
Materials: wood/plastic samples, glues, weights.
Method: Glue samples and test load until failure.
Learn: Materials testing and adhesives chemistry. - Investigate Insulator vs Conductor in Homemade Circuits
Objective: Compare wire types and connectors for resistance.
Materials: wires, resistors, battery, LED, multimeter.
Method: Build circuits and measure voltage/current.
Learn: Basic circuits and resistance. - Build a Simple Seismograph Model
Objective: Design a model seismograph that records vibrations.
Materials: base, hanging mass, pen, paper.
Method: Shake base and record motion traces.
Learn: Earthquake measurement and damping. - Design and Test a Shoe Sole for Better Grip
Objective: Create patterns and test slip resistance.
Materials: rubber sheets, textured stamps, incline plane with water.
Method: Test slip angle for different patterns.
Learn: Product design and materials testing. - Solar Tracker Model: Does Tracking Increase Panel Output?
Objective: Compare fixed vs tracking small panel output.
Materials: small panels, motors/sensors or manual tracking setup.
Method: Measure output over day for fixed vs tracked panels.
Learn: Solar tracking benefits.
Computer Science & Math (10 ideas)
- Which Sorting Algorithm Is Faster for Small Data? (Simulation)
Objective: Compare bubble sort vs insertion sort on small lists (program).
Materials: computer, coding environment (Scratch, Python).
Method: Time sorts on lists of different sizes and analyze.
Learn: Algorithms and complexity basics. - Predicting Local Weather with Simple Models
Objective: Use past temp/rain data to make simple predictions.
Materials: local weather data, spreadsheet.
Method: Create linear models and test accuracy on holdout data.
Learn: Data analysis and modeling basics. - How Does Screen Time Affect Reaction Time? (Survey + Test)
Objective: Collect data on screen time and test reaction times.
Materials: survey, ruler drop test, volunteers.
Method: Correlate screen time with measured reaction times.
Learn: Correlation vs causation and basic stats. - Image Compression: How Much Quality Can You Lose?
Objective: Test JPG quality settings and human detectability.
Materials: images, software, volunteers.
Method: Save images at different compressions and ask volunteers which are visibly worse.
Learn: Digital image concepts and perceptual thresholds. - Maze Solving Algorithms with Robots or Simulations
Objective: Compare right-hand rule vs breadth-first search in a simple maze robot or simulation.
Materials: robot kit or simulation software.
Method: Run algorithms and measure steps/time taken.
Learn: Pathfinding and algorithm performance. - Effect of Sample Size on Survey Accuracy (Simulated)
Objective: Simulate polls with different sample sizes and compare error.
Materials: computer or spreadsheet.
Method: Simulate random sampling from a population and measure variance.
Learn: Statistics and sampling error. - Does Handwriting vs Typing Affect Memory?
Objective: Test recall of words written by hand vs typed.
Materials: volunteers, tests, timer.
Method: Have groups study words either handwritten or typed and test recall.
Learn: Cognitive differences and study techniques. - How Does Encryption Strength Affect Time to Crack? (Simulated)
Objective: Simulate simple ciphers and brute force times.
Materials: computer and simple scripts.
Method: Try to break Caesar vs Vigenère cipher with brute force and measure time.
Learn: Cryptography basics. - Modeling Population Growth: Exponential vs Logistic
Objective: Use spreadsheet to model populations under different conditions.
Materials: spreadsheet, scenario data.
Method: Build models and compare to idealized data.
Learn: Mathematical modeling and carrying capacity. - Which Factors Improve Typing Speed Most?
Objective: Test keyboard layout, practice time, and posture effects on typing speed.
Materials: typing test site, volunteers.
Method: Measure WPM under varied conditions and compare results.
Learn: Human factors and ergonomics.
Food, Nutrition & Health (10 ideas)
- Comparing Sugar Content of Homemade vs Store-Bought Smoothies
Objective: Compare sugar levels using simple Brix refractometer or nutrition labels.
Materials: refractometer (or labels), smoothie samples.
Method: Measure sugar content and compare per serving.
Learn: Nutrition and hidden sugars. - How Does Cooking Method Affect Vitamin Content (Model with Heat-Sensitive Vitamin)
Objective: Test vitamin C loss in vegetables boiled vs steamed.
Materials: veggies, cooking tools, iodine test or indicator (supervised).
Method: Cook and compare nutrient estimates.
Learn: Nutrient loss and cooking methods. - Which Preservative Extends Fruit Freshness Best?
Objective: Test lemon juice, sugar syrup, refrigeration.
Materials: fruit slices, treatments, fridge, observation log.
Method: Treat slices and record spoilage.
Learn: Food preservation basics. - Test Yogurt Cultures: Which Milk Produces the Thickest Yogurt?
Objective: Compare cow, goat, and plant milks for yogurt texture.
Materials: milk types, starter culture, incubator.
Method: Make yogurts and measure viscosity or thickness.
Learn: Fermentation and dairy science. - Does Color of Plate Affect Perceived Sweetness?
Objective: Test whether plate color changes taste perception.
Materials: same snacks on different colored plates, volunteers.
Method: Blind taste tests and rating scales.
Learn: Psychology of taste and color effects. - How Long Do Common Household Germs Survive on Different Surfaces?
Objective: Use safe indicators (like harmless yeast or simulated markers) to compare survival.
Materials: safe cultures or simulated markers, surfaces.
Method: Apply marker and test transfer after set times.
Learn: Surface persistence and hygiene. - Comparing Energy Content of Snacks by Burn Test (Calorimetry Model)
Objective: Compare approximate calories by burning small samples and measuring temp change in water (classroom-safe model).
Materials: small calorimeter setup, snacks, thermometer.
Method: Burn sample and measure water temp rise.
Learn: Energy content basics (safety supervised). - Effect of Sleep on Short-Term Memory Recall
Objective: Test student recall after different sleep durations (self-reported).
Materials: short memory tests, volunteers.
Method: Measure recall performance under different sleep conditions.
Learn: Sleep impact on cognition. - Which Breakfast Improves Concentration in Morning Tests?
Objective: Compare test scores after different breakfast types (protein vs carbs).
Materials: simple quizzes, volunteers, food control.
Method: Randomly assign breakfasts and measure quiz performance.
Learn: Nutrition and cognitive performance. - Testing Electrolyte Drinks: Which Rehydrates Faster?
Objective: Compare water vs sports drink rehydration (weight-based or thirst scale under supervision).
Materials: volunteers, drinks, scales.
Method: Measure weight change or endurance in light exercise.
Learn: Hydration science and electrolyte balance.
Behavioral & Psychology (10 ideas)
- Do People Prefer High or Low Pitch Voices for Instruction?
Objective: Test clarity preference for different voice pitches.
Materials: recorded instructions, volunteers, surveys.
Method: Play recordings and ask volunteers to rate clarity and preference.
Learn: Perception and communication. - How Color Affects Mood (Simple Survey Test)
Objective: Test mood before/after exposure to colored rooms or images.
Materials: pictures of colors, mood surveys.
Method: Show colors and record mood ratings.
Learn: Color psychology basics. - Memory: Do Rhymes Improve Recall?
Objective: Compare recall of facts presented as prose vs rhymes.
Materials: word lists or facts, volunteers.
Method: Test recall after short delay.
Learn: Mnemonics and memory strategies. - Does Smiling Improve Problem Solving Under Stress?
Objective: Test problem performance with forced smile vs neutral expression under mild stress (ethical and safe).
Materials: puzzles, volunteers.
Method: Assign expressions and time problem solving.
Learn: Mood effects on cognition. - Which Type of Reward Motivates Students More? (Stickers vs Praise)
Objective: Measure task performance improvement after different rewards.
Materials: small tasks, reward types, volunteers.
Method: Compare task speed/accuracy across reward conditions.
Learn: Motivation theory basics. - Effect of Background Noise on Reading Comprehension
Objective: Test reading tests under quiet vs noisy backgrounds.
Materials: reading passages, audio noise, timers.
Method: Measure comprehension scores.
Learn: Attention and distraction. - Does Peer Presence Affect Performance?
Objective: Test if students do better when observed or alone.
Materials: standardized tasks, volunteers.
Method: Compare performance under both conditions.
Learn: Social facilitation. - Which Learning Style Helps Retention Most: Visual vs Auditory?
Objective: Teach short material visually or by audio and test recall.
Materials: study materials, volunteers.
Method: Assign groups and test retention.
Learn: Learning modality effects. - Color of Light and Productivity for Homework Tasks
Objective: Test homework accuracy under cool vs warm light.
Materials: lamps of different color temps, tasks.
Method: Measure speed and correctness.
Learn: Lighting and concentration. - Does Word Choice Affect Persuasion (Simple Ads Test)
Objective: Test two ad wordings and see which convinces more peers.
Materials: two ad scripts, volunteers, survey.
Method: Present ads and record persuasion ratings.
Learn: Language and persuasion.
Botany & Gardening (10 ideas)
- Which Compost Mix Produces Healthier Seedlings?
Objective: Compare compost mixes (leaf, manure, mixed).
Materials: compost types, seeds, pots.
Method: Grow seedlings and measure growth and vigor.
Learn: Soil nutrition and plant health. - Vertical Garden: Which Plant Spacing Produces Best Yield?
Objective: Test spacing on growth and yield per area.
Materials: vertical planters, seedlings.
Method: Plant at different spacings and measure yield.
Learn: Space optimization. - Hydroponics vs Soil: Plant Growth Comparison
Objective: Compare growth rates of same plant in hydroponic and soil systems.
Materials: simple hydroponic setup, pots, plants.
Method: Keep nutrients controlled and measure growth.
Learn: Growing systems and nutrient delivery. - Does Music Affect Seed Germination Rate?
Objective: Play music to one group of seeds and silence to control.
Materials: seeds, speakers.
Method: Track germination percentage and timing.
Learn: Environmental stimuli effects. - Test the Effect of Companion Planting on Pest Reduction
Objective: Plant companion pairs and monitor pest levels.
Materials: garden plots, plants, pest count log.
Method: Compare pest presence on companion vs single plantings.
Learn: Companion planting and integrated pest management. - Which Mulch Color Warms Soil Most in Spring?
Objective: Measure soil temperature under dark vs light mulch.
Materials: mulches, thermometers, pots.
Method: Cover soil and record temps over days.
Learn: Soil warming and planting timing. - Testing Different Watering Schedules for Tomatoes
Objective: Find which schedule yields best fruit production.
Materials: tomato plants, watering plans, scale.
Method: Track fruit count and weight over season.
Learn: Water management and yield. - Effect of pH on Seedling Growth
Objective: Test seedling growth in soils adjusted to different pH levels.
Materials: soil, pH adjusters, seedlings.
Method: Grow and measure health/growth.
Learn: pH effects on nutrient uptake. - Which Fertilizer Increases Flowering Most?
Objective: Compare nitrogen vs phosphorus rich fertilizers.
Materials: fertilizers, flowering plants.
Method: Apply and count blooms.
Learn: Plant nutrition and reproduction. - Testing Shade Cloth Densities for Garden Yield
Objective: Compare yields under different shade percentages.
Materials: shade cloths, plants, yield measurement.
Method: Measure growth and produce under varied shade.
Learn: Light management in horticulture.
Miscellaneous, Materials & Technology (20 ideas)
- Testing Ink Drying Times on Different Papers
Objective: Compare how fast ink dries on coated vs uncoated papers.
Materials: pens, papers, timer.
Method: Mark and touch at intervals to test smudging.
Learn: Material absorption and ink chemistry. - How Does Humidity Affect Static Electricity?
Objective: Test static charge strength in different humidity.
Materials: balloon, wool, humidity meter or humidifier.
Method: Charge balloon and measure attraction at varying humidity.
Learn: Electrostatics and humidity. - Testing Strength of Homemade Glues (Flour vs Glue vs Hot Glue)
Objective: Compare bond strength of adhesives.
Materials: sample joints, glues, weights.
Method: Load until failure and record strengths.
Learn: Adhesive properties. - Which Marker Erases Best from Dry Erase Board?
Objective: Compare erasability of markers by brand/type.
Materials: markers, dry erase board, cleaning solution.
Method: Write, wait, and attempt to erase; rate residue.
Learn: Material compatibility. - Modeling Tsunami Wave Height vs Underwater Slope (Wave Tank)
Objective: Use wave tank to model slope effects on wave amplification.
Materials: shallow tank, wave maker, slopes of sand/boards.
Method: Generate waves and measure heights at shore.
Learn: Coastal science and wave behavior. - Test Which Paper Insulates Sound Best
Objective: Layer papers and measure sound transmission.
Materials: speaker, microphone, papers.
Method: Test decibel reduction through layers.
Learn: Acoustic insulation. - Which Bubble Solution Makes Biggest Bubbles?
Objective: Compare recipes (soap ratios, glycerin).
Materials: soaps, glycerin, water, wand.
Method: Make solutions and measure bubble size and longevity.
Learn: Surface tension and polymers. - Investigate How Color of Clothing Affects Body Temperature in Sun
Objective: Measure temp under different colored fabrics.
Materials: fabric swatches, thermometer, heat lamp.
Method: Place sensor under fabrics in lamp and record temps.
Learn: Heat absorption and clothing design. - Testing the Strength of Different Knot Types
Objective: Compare breaking strength of knots.
Materials: rope, weights or hook.
Method: Tie knots, load until failure, record max weight.
Learn: Practical mechanics and knot efficiency. - Making and Testing a DIY Water Filter for Microplastics
Objective: Build filters and test microplastic capture using visible fibers.
Materials: filter stages, water with fibers, microscope observation.
Method: Filter and examine captured fibers.
Learn: Filtration and environmental engineering. - Investigate Candle Burn Rate Under Different Draft Conditions
Objective: See how breeze affects candle burn.
Materials: candles, fan, timer, measuring.
Method: Burn under still vs breezy conditions and measure mass loss.
Learn: Combustion and airflow. - Test Reflective Tape Brightness at Night
Objective: Compare visibility of tapes under car headlights.
Materials: reflective tape samples, flashlight or car, distance markers.
Method: Measure distance at which tape becomes visible.
Learn: Safety materials and reflectivity. - Compare Thermal Expansion of Metals
Objective: Measure length change of metal rods when heated.
Materials: metal rods, heat source, caliper.
Method: Heat and measure expansion carefully.
Learn: Thermal expansion coefficients. - Which Ingredient Affects Homemade Slime Stretchiness Most?
Objective: Test starch, glue amount, or borax levels.
Materials: slime ingredients, measuring tools.
Method: Make slimes with variations and measure stretch length.
Learn: Polymers and crosslinking. - How Do Different Textures Affect Adhesion of Tape?
Objective: Test tape stickiness on smooth vs rough surfaces.
Materials: tape, surfaces, scale for pull test.
Method: Apply tape and measure force to peel off.
Learn: Adhesion and surface contact. - Comparing UV Blocking of Different Sunglasses
Objective: Test UV transmission using UV meter or UV beads.
Materials: sunglasses samples, UV beads or meter.
Method: Expose beads/meter under sunglasses and record UV passing.
Learn: Optics and eye protection. - Test Which Sponges Hold Most Water
Objective: Compare water retention across sponge types.
Materials: sponges, water, scale.
Method: Soak, weigh, then squeeze and weigh again.
Learn: Porosity and absorption. - Investigate the Effect of Magnet Strength on Compass Deflection
Objective: Measure compass deflection at different magnet distances.
Materials: compass, magnets, ruler.
Method: Move magnet and record angle change.
Learn: Magnetic field strength and navigation. - What Kitchen Material Conducts Heat Fastest?
Objective: Test pans of different materials (aluminum, stainless, cast iron) by heating and measuring temp rise.
Materials: small pan samples, burner, thermometer.
Method: Heat each and note how fast they reach certain temps.
Learn: Thermal conductivity in cookware. - Design a Reusable Water Bottle That Keeps Water Cold Longest
Objective: Compare sample insulating designs (double wall, vacuum, foam).
Materials: bottle prototypes or existing bottles, ice, thermometer.
Method: Fill with ice water and measure temp change over hours.
Learn: Insulation and product testing.
Must Read: 99+ Easy Class 12 Physics Investigatory Project Topics 2026
Conclusion & Final Tips
You now have 150 science fair project ideas for 7th grade to pick from, grouped by topic and ready to use. Here are final tips to turn any idea into a great science fair project:
- Narrow your question. Turn a general idea into a specific testable question (example: “Which soil holds water best?” rather than “How does soil work?”).
- Make a clear hypothesis. State what you expect to happen and why, using your background research.
- Plan your procedure with controls. Decide how many trials you’ll run (3 is typical) and how you’ll keep variables consistent.
- Collect data carefully. Use tables and take photos. Raw data matters.
- Analyze results with graphs. Bar graphs and line charts help judges quickly see your findings.
- Explain your conclusion. Say whether your hypothesis was supported and why the results likely happened. Suggest improvements or future tests.
- Practice your presentation. Be ready to explain your project in plain language and answer questions about your process and results.
Good luck picking a project — pick something you’re excited about, plan carefully, and have fun discovering real science. If you want, tell me which category you like and I’ll help you turn one idea into a full plan with a materials list, step-by-step procedure, data table template, and display board text.
