1029 science project ideas, from class 1 to college.

What it shows

The depth and amount of soil limit how far roots can spread. Growing the same bean in a tall cup and a short cup shows how room for roots affects the plant above ground.

You will need

• Two clear plastic cups of the same width but different height (or one cup cut shorter)
• Garden soil, enough to fill each cup to 1 cm below the rim
• 4 soaked bean or gram seeds
• A marker and a ruler
• A measuring cup for water
• A notebook

Safety: An adult must cut the cups and make drainage holes. Wash your hands after handling soil.

Take it further: Make a third cup with soil only half full and see whether the roots reach the bottom sooner and what that does to growth.

What it shows

A water plant in bright light gives off bubbles of oxygen, because it is making food by photosynthesis. The closer the lamp, the faster the bubbles stream, until another factor limits the rate.

You will need

• A fresh sprig of Hydrilla or another oxygen weed from a pond or aquarium shop
• A large clear glass or beaker
• A glass funnel or a cut clear bottle top
• A small test tube or clear bottle
• A pinch of baking soda
• A table lamp with an LED bulb (not a hot bulb)
• A metre ruler
• A watch or phone timer

Safety: Do not drink the water. An adult must cut the bottle. Use an LED lamp so the water does not heat up, and keep the lamp and plug away from water. Wash hands after touching pond plants.

Take it further: Keep the lamp fixed and warm the water in steps of 5 degrees Celsius in a bowl of warm water to see how temperature affects the bubble rate.

What it shows

The green colour of a leaf is a mixture of several pigments. When the extract climbs a strip of paper, the pigments travel different distances and show as bands of green, yellow and orange.

You will need

• A few fresh spinach or lettuce leaves
• A coin or the back of a spoon for crushing
• About 10 mL of rubbing alcohol (isopropyl) or surgical spirit
• A strip of coffee filter paper or chromatography paper 2 cm wide and 15 cm long
• A tall glass or clear jar
• A pencil and a clip or clothes peg
• A small cup and a spoon

Safety: Rubbing alcohol is flammable and its fumes irritate. An adult must handle it, keep it away from flames, work with windows open, and keep it off skin and eyes. Do not use any flame or heater.

Take it further: Compare a green leaf with a fallen yellow leaf and look at which pigments are left in the autumn leaf.

What it shows

Leaves lose water to the air, mostly through their stomata. Weighing different leaf types over two days shows how leaf structure affects water loss.

You will need

• One leaf each from spinach, mint, guava and a thick leaf such as jade plant or aloe tip (4 leaf types)
• A digital kitchen or jewellery scale reading to 0.1 g
• A tray lined with a paper towel
• A marker and a notebook
• Paper clips or small labels
• A ruler

Safety: Wash your hands after handling plants and do not eat any leaves used. An adult must cut leaves from plants you do not own.

Take it further: Smear petroleum jelly on the upper side of a second leaf of each type, and see how much it cuts the water loss.

What it shows

A potometer measures how fast a cut shoot takes up water, which is close to how fast it transpires. Changing wind or light shows which factors speed water loss from leaves.

You will need

• A leafy twig 20 cm long, such as balsam, coleus or mint
• A 5 mL syringe without a needle
• About 30 cm of clear aquarium air tube that fits the syringe tip
• A basin of water and a few drops of food colour
• A ruler or a printed 1 mm scale
• A small table fan
• Petroleum jelly and a clamp or stand
• A stopwatch or phone timer

Safety: An adult must cut the twig with secateurs and handle the fan, keeping it away from water and wires. Do not use mains-powered equipment near spills.

Take it further: Compare the rate for the same shoot before and after you strip off half of the leaves, and calculate rate per unit leaf area.

What it shows

The lower surface of many leaves is dotted with tiny pores called stomata, each between two bean-shaped guard cells. Counting them under a microscope shows where a leaf exchanges gases and water vapour.

You will need

• A fresh Rhoeo (boat lily) or Tradescantia leaf
• A school compound microscope or a phone with a clip-on magnifier lens
• Glass slides and cover slips (or clear tape and a microscope slide)
• A dropper and water
• A fine paintbrush
• Tweezers and a blotting paper
• A notebook for sketches

Safety: Glass slides and cover slips break easily and an adult must supervise their use. An adult must help with the blade, if one is used, to tear or cut the leaf. Wash your hands after handling plants.

Take it further: Compare the stomata density of a Rhoeo leaf with that of a thick succulent such as a jade leaf, which usually has fewer.

What it shows

Each eye has a small spot with no light-sensing cells, where the optic nerve leaves the eye. A card with a cross and a dot lets you find the distance at which the dot disappears.

You will need

• A white card of about 10 cm by 15 cm
• A black marker
• A ruler
• A friend or family member to test
• A notebook
• A tape measure or a metre scale

Take it further: Draw a long line with a gap on a card and see whether the brain fills in the gap when the line crosses the blind spot.

What it shows

The old school picture of a tongue with separate zones for each taste is a myth. Testing tastes on different parts of the tongue shows that every part can detect all the basic tastes.

You will need

• Four cups of mild test liquids: sugar water, salt water, diluted lemon juice and weak tea or diluted bitter gourd juice
• Clean cotton buds, one for each test and each person
• Plain water to rinse the mouth
• A printed tongue outline for each volunteer
• Coloured pencils
• Two or three willing volunteers
• A notebook

Safety: Use only food-safe liquids and a fresh cotton bud every time. Check for allergies first, and wash hands. Use no strong, hot or unusual liquids. An adult must supervise.

Take it further: Test taste with the nose pinched and see how much the flavour of a flavoured sweet changes.

What it shows

Our skin is not equally sensitive everywhere. The smallest gap at which a person feels two points instead of one shows where touch receptors are packed more closely.

You will need

• Two blunt wooden toothpicks or two bent paper clips with rounded ends
• A ruler with millimetre marks
• A blindfold or a sleeve to block vision
• A partner volunteer
• A notebook with a ready table
• Cardboard strip with pairs of holes 2, 5, 10, 20 and 40 mm apart (optional)

Safety: Use only blunt points and the lightest touch. Stop if the volunteer feels any pain. An adult must supervise.

Take it further: Test whether the gap gets smaller after a fingertip is held in cool water for one minute, and discuss why temperature may matter.

What it shows

A dropped ruler measures how fast your nerves and muscles respond. How far the ruler falls before you catch it gives your reaction time, and you can test how practice or a second task changes it.

You will need

• A 30 cm ruler
• A partner
• A table and chair
• A notebook and a calculator
• A phone calculator or a printed table of distance and time
• A few easy questions or a counting task for distraction

Safety: Sit down during the test and keep the ruler soft and light. An adult should supervise.

Take it further: Compare reaction times of the same people when they are fresh in the morning and when tired in the evening.

What it shows

The air you breathe out can be measured by the water it pushes out of an upturned bottle. It gives your tidal volume and your vital capacity, and shows how they compare between people.

You will need

• A 2 litre clear plastic bottle with a marked scale you make by pouring in known volumes
• A large basin or tub
• About 1 metre of clean plastic tubing
• A permanent marker and a measuring jug
• A fresh disposable straw cut to length, one for each person
• Soapy water and a clean cloth
• A notebook

Safety: Use a fresh straw for every person and wash the tube end with soapy water between users. Do not test anyone with asthma, a cold or breathing trouble. Stop at once if anyone feels dizzy; an adult must supervise.

Take it further: Compare vital capacity before and after four weeks of daily breathing and stretching exercise among willing volunteers.

What it shows

Muscles in exercise need more oxygen and glucose, so the heart beats faster. The time that the pulse takes to come back to normal shows how quickly the body recovers.

You will need

• A watch or phone stopwatch
• A chair and a clear space for stepping on and off a low step 20 cm high
• A notebook and graph paper
• A friend to record the times
• Water for drinking after the test
• A pencil

Safety: Take part only if you are well, and skip the exercise if you have any heart, breathing or health condition. Stop if you feel dizzy, and have an adult supervise at all times.

Take it further: Test how the pulse rises after different amounts of exercise, such as 30 seconds, 1 minute and 2 minutes of stepping, on different days.

What it shows

Foods and drinks can stain the surface of teeth, and brushing removes the stain. Stained eggshells stand in for teeth to compare rinsing, brushing with water and brushing with toothpaste.

You will need

• 4 clean eggshell halves from boiled eggs
• A cup of strong, cooled tea
• An old soft toothbrush for each test
• Toothpaste
• A timer
• Four cups for rinsing
• A notebook and a white card for comparing colours

Safety: An adult must pour hot tea and cool it before use. Do not use the eggshells or the brush in the mouth afterwards. Wash hands after touching eggshell.

Take it further: Compare a soft brush with a hard-bristled brush on stained shells and find out which leaves more scratches under a magnifier.

What it shows

The inside of the small intestine is covered with finger-like villi that give it a very large surface area for absorbing food. A looped towel soaks up much more water than a flat cloth of the same size, just as a villus-lined gut absorbs more.

You will need

• A flat piece of cotton cloth, 10 cm by 10 cm
• A piece of terry towel, 10 cm by 10 cm
• Water with a few drops of food colour
• A kitchen scale that reads to 0.1 g
• A shallow dish
• A timer
• A notebook
• String or a long cloth strip for the small intestine length model

Safety: An adult must cut the cloth and supervise the scissors. Keep the scale dry.

Take it further: Measure the length of the wrinkles in a folded cloth against a flat cloth to calculate how folding increases the area.

What it shows

Foods that contain fat leave a see-through greasy mark on brown paper that does not dry away. A quick rub test sorts foods into those with fat and those without.

You will need

• A sheet of plain brown paper or a paper bag cut into squares
• Food samples: sesame seeds, a potato chip, a piece of apple, a biscuit, a few drops of oil or ghee and a boiled sweet
• A little plain water as a control
• A pencil to label
• A mortar or a spoon to crush seeds
• A window or a lamp
• A notebook

Safety: Check that no one has a nut or seed allergy before using any nuts. Wash hands afterwards. An adult must supervise.

Take it further: Rub equal-sized pieces of different chips and compare the size of the grease spots to rank which has the most fat.

What it shows

Yeast makes dough rise by fermenting sugar and giving off carbon dioxide. Adding more salt to the dough slows the yeast, so the dough rises less.

You will need

• 4 equal clear tall glasses or cut bottles
• Plain flour (maida or atta), 200 g
• Dry baker’s yeast, 4 small pinches
• Sugar, 4 level teaspoons
• Salt, in measured amounts of 0 g, 0.5 g, 1 g and 2 g
• Warm water (about 30 to 35 degrees Celsius), 120 mL
• A ruler and rubber bands to mark height
• A kitchen scale

Safety: An adult must warm the water, because it must not be hot. Do not eat the raw dough. Wash hands and surfaces after handling it.

Take it further: Keep the salt fixed and repeat with different amounts of sugar to see where the rise is the greatest.

What it shows

Ripening fruits release a gas called ethylene that makes nearby fruit ripen faster. Green bananas sealed with a ripe fruit ripen sooner than bananas left on their own.

You will need

• 6 green bananas of the same bunch (or small raw mangoes)
• 1 ripe banana or apple
• Three paper bags or loosely tied plastic bags
• A marker and labels
• A colour chart of 1 to 7 stages (green to brown speckled), which you draw
• A notebook
• A camera or phone for daily photos

Safety: Wash hands after handling fruit. Do not eat any fruit that smells fermented or has gone mouldy; ask an adult to throw it away.

Take it further: Compare ripening in a refrigerator and at room temperature, and record how cold changes the speed.

What it shows

Rice and urad dal batter swells and turns sour overnight because tiny microbes in it make gas and acid. The rise is faster in a warm place than in a cool one.

You will need

• Fresh idli or dosa batter, ground by an adult at home (about 1 cup)
• Two identical tall clear jars or steel vessels with lids
• A ruler and a rubber band to mark the level
• A kitchen thermometer (non-mercury)
• A warm spot (near a cooker) and a cooler spot (floor of a cool room)
• A notebook for the diary

Safety: An adult must grind the batter and handle any hot cooking area. Do not taste the batter if it smells bad or has pink or black patches; throw it away. Wash hands and jars after the test.

Take it further: Find out how the batter rises with a pinch of salt added, and check whether salt makes it slower or faster.

What it shows

Milk turns into curd because friendly bacteria in a spoon of old curd turn milk sugar into lactic acid. Keeping the milk at different temperatures shows how heat changes the speed of this change.

You will need

• Half a litre of milk, boiled by an adult and cooled
• A teaspoon of fresh curd as a starter for each jar (3 teaspoons in all)
• Three clean small steel vessels or glass jars with lids
• A thermometer (non-mercury)
• A warm insulated box or a pot with a towel
• A refrigerator or a cooler corner
• A watch and a notebook

Safety: An adult must boil the milk and pour it. Check that the milk feels only lukewarm on your wrist. Use clean spoons and jars, and throw away milk that smells bad. Wash hands.

Take it further: Compare the setting time with different amounts of starter (half a teaspoon, one and two) in the same warm place.

What it shows

Many flowers depend on insects, birds or bats to move pollen so they can make fruit. Counting visitors on two kinds of flower at different times of day shows which flowers and hours are busiest.

You will need

• Two flowering plants of different colours in a garden or a park, for example a yellow marigold and a pink balsam
• A notebook and a pencil
• A phone timer or a watch
• A pre-ruled tally sheet
• A hat and a plastic stool
• A camera (optional)

Safety: Stay a metre away and never touch, catch or disturb the insects, because bees and wasps can sting. Do not do this if you have a bee-sting allergy. Tell an adult where you are and sit quietly.

Take it further: Compare a patch with a nearby building or pesticide-free corner to see whether surrounding conditions change the number of visitors.

What it shows

Microbes in a compost heap give off heat as they break down waste. A balanced mix of green and brown material, kept moist and aerated, warms up more than green waste alone.

You will need

• Two 10 litre buckets with holes drilled in the sides and the bottom
• Green waste: vegetable and fruit peels, tea leaves (no meat, dairy or cooked food)
• Brown waste: dry leaves, paper torn small, coir
• A thermometer reading to 0.5 degrees Celsius (non-mercury)
• A garden trowel and gloves
• A spray bottle for water
• A notebook

Safety: An adult must drill the holes. Wear gloves and wash hands after handling compost, and wear a mask when turning dry, dusty material. Keep the buckets away from food. Do not add meat, dairy or pet waste.

Take it further: Repeat with different ratios of brown to green, such as 1:1, 2:1 and 3:1, and find which gives the greatest rise.

What it shows

Fallen leaves are broken down by fungi, bacteria and soil animals. Burying equal weights of different leaves in mesh bags and weighing them later shows which kinds decompose faster.

You will need

• Dry fallen leaves of four kinds, for example neem, mango, banyan and teak, or any that you can find
• Four to eight small mesh bags (onion bags or net cloth) about 10 cm by 10 cm
• A scale reading to 0.1 g
• A garden trowel and gloves
• Waterproof labels or plastic tags and string
• A garden bed or large pot of soil
• A notebook

Safety: Wear gloves and wash hands after handling soil and leaves. An adult must supervise the digging if you use tools.

Take it further: Bury another set in a dry sandy soil and compare the loss to the moist garden bed.

What it shows

The roots of pulse plants such as gram, pea and groundnut carry small lumps called nodules in which bacteria fix nitrogen from the air. That is why pulses are rotated with cereals to keep soil fertile.

You will need

• A whole gram, pea, groundnut or moong plant with its roots (with the owner’s permission)
• A wheat or grass plant for comparison
• A trowel and a bucket of water
• A hand lens or a magnifying glass
• A sheet of white paper
• A sharp knife for the adult only
• A notebook and coloured pencils

Safety: Take plants only with permission, dig carefully, and wash your hands afterwards. An adult must slice any nodule with the knife.

Take it further: Compare nodule number on plants from a fertiliser-rich bed and a poor bed, and discuss what you see.

What it shows

The thin skin of an onion layer is a sheet of box-like plant cells. A stained slide under the microscope shows the cell wall and the nucleus, and a simple trick lets you estimate how big each cell is.

You will need

• An onion
• A school compound microscope
• Glass slides and cover slips
• Tweezers, a dropper and a blotting paper
• Dilute iodine solution (a few drops of tincture of iodine in a cup of water) or a drop of red ink in water
• A transparent ruler marked in millimetres
• A pencil and a notebook

Safety: An adult must cut the onion, prepare the dilute iodine and supervise. Iodine stains skin and clothes and must not be swallowed; keep it away from eyes. Glass slides break easily. Wash hands after the practical.

Take it further: Compare onion cells with a thin leaf peel from a plant such as Rhoeo and note the difference, such as green chloroplasts.