Biology
Biology projects for class 9 and 10: 77 ideas.
Each project below opens to its own page with what it shows, the science behind it, the materials, safety, step-by-step instructions, what you should see and viva questions. Many can be made from things at home; where a kit helps, the page links one.
Other subjects for class 9 and 10: Physics, Chemistry, Maths, Earth and space, Electronics and robotics, Environment, Computing and coding.
Human digestive system model
Food travels from the mouth down the food pipe to the stomach, the small intestine and the large intestine. The liver and pancreas add juices that help digestion.
Working lungs model
Pulling the diaphragm (the stretched balloon) down makes more space in the chest, the air pressure inside drops, and air rushes into the lungs. Pushing it back up pushes the air out.
Human heart model with double circulation
The heart has four chambers. The right side pumps blood to the lungs to pick up oxygen, and the left side pumps it to the rest of the body. Valves stop the blood flowing backwards.
Plant and animal cell models
Both cells have a nucleus, cytoplasm and a cell membrane. Plant cells also have a cell wall, chloroplasts and a large vacuole.
DNA double helix model
DNA is two strands twisted into a double helix. The sides are sugar and phosphate; the rungs are pairs of bases, with A always joined to T and G to C.
Reflex arc model
In a reflex, such as pulling your hand away from something hot, the message travels from the receptor to the spinal cord and straight back to the muscle, before the brain has time to think.
Does the colour of light affect plant growth?
Chlorophyll absorbs red and blue light strongly and reflects most green light, so seedlings under green filters usually grow more weakly than those in white light.
Yeast fermentation and temperature
Yeast feeds on sugar and gives off carbon dioxide gas, which inflates a balloon fastest in warm water. Cold slows the yeast down and very hot water kills it.
Osmosis in potato strips
Water moves through cell membranes from a weaker solution to a stronger one (osmosis). Potato strips in strong salt or sugar water lose water and shrink; strips in plain water take in water and firm up.
Extract DNA from a banana
Washing-up liquid breaks open the cell membranes, salt helps the DNA clump together, and ice-cold alcohol makes the DNA come out of solution as white strands you can see.
Foil on a leaf: where does the plant store starch?
A leaf partly covered with foil for two days and then tested with iodine turns blue-black only where light reached it. Leaves make starch by photosynthesis, and photosynthesis needs light.
Tall cup and short cup: does root room change growth?
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.
Counting oxygen bubbles from Hydrilla at different light distances
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.
Spinach leaf pigments separated on filter paper
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.
Detached leaves left on a tray: which type loses weight fastest?
Leaves lose water to the air, mostly through their stomata. Weighing different leaf types over two days shows how leaf structure affects water loss.
Rhoeo leaf peel: counting stomata and guard cells
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.
Ear model with a funnel and balloon eardrum and dancing salt
Sound is collected by the outer ear and makes the eardrum vibrate. A balloon stretched over a tube acts as the eardrum, and grains of salt dance on it when you speak into the funnel.
Shoebox eye model with a lens that shows an upside-down image
The eye works like a camera. A lens at the front focuses light from the world onto a screen at the back, giving a small image that is upside down.
Is there a tongue map? Testing sweet, salt, sour and bitter
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.
Two-point touch test on fingertip, palm and forearm
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.
Ruler-drop reaction time: does practice or distraction change it?
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.
Lung volumes measured by water displacement in a bottle
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.
Pulse rate before and after exercise: a recovery graph
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.
Kidney filtration model with a strainer, cloth and funnel
The kidney filters blood: small molecules such as water, salt and sugar pass out, while blood cells and large proteins are held back. A layered funnel shows the filtering idea step by step.
Vein valve model: how muscle squeezes push blood one way
Veins have valves that let blood flow only towards the heart. A tube with a one-way valve and a squeezing hand shows how muscles help push blood back up the legs.
Villi and surface area: flat cloth against a looped towel
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.
Fat spot test on brown paper: nuts, snacks, fruit and sweets
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.
Salt and yeast: how much does salt slow a rising dough?
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.
Banana ripening in bags: does a ripe fruit speed it up?
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.
Idli batter rise diary: a warm corner against a cool corner
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.
Curd setting time at three temperatures
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.
Closed bottle garden that recycles its own water
A sealed jar with soil and plants keeps its own small water cycle. Water evaporates from the soil and leaves, condenses on the glass and runs back, while plants and soil life swap oxygen and carbon dioxide.
Flower visitor watch: counting pollinator visits by colour and time of day
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.
Compost bucket temperature log: green waste against a green and brown mix
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.
Leaf litter in mesh bags: which leaves rot fastest in soil?
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.
Root nodules on a pulse plant: tiny nitrogen factories
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.
Onion peel slide: cell wall, nucleus and the size of one cell
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.
Catalase in potato: raw, boiled and crushed pieces make different foam
Living cells make an enzyme, catalase, that breaks hydrogen peroxide into water and oxygen. Raw potato foams strongly when added to dilute peroxide, boiled potato hardly foams, and crushed potato foams fastest.
Fresh and tinned pineapple in jelly: an enzyme that eats protein
Fresh pineapple contains bromelain, an enzyme that breaks down proteins, so it stops gelatin jelly from setting. Tinned or boiled pineapple, whose enzyme has been destroyed by heat, lets the jelly set normally.
Mendel with coins: tossing a pea cross to find the 3 to 1 ratio
When two hybrid tall pea plants are crossed, each offspring gets one gene copy from each parent at random. Tossing two coins 100 times copies this and shows the 1 to 2 to 1 genotype and 3 to 1 appearance ratios.
Kidney filter model with sand, gravel and cotton in a bottle
The kidney filters blood: large particles stay in, and water, salts and urea leave as urine. The layered bottle shows filtering by particle size.
Blood circulation model with a squeeze-bottle heart and coloured water
The heart pumps blood in a loop through the lungs and the body, and valves make it flow one way. The model shows double circulation with a pump and two tube loops.
Model of the human eye with a water-filled bottle lens
The eye lens forms an upside-down image on the retina, and the brain turns it upright. A water lens and screen show how focus works and why spectacles help.
Layered foam sheet model of a leaf cross-section with stomata
A leaf has an epidermis, palisade cells full of chloroplasts, loose spongy cells with air spaces, veins and stomata. The layers are built to catch light and let gases move.
Dough rise measured with a rubber band: sugar and salt effects
Yeast in dough eats sugar and gives out carbon dioxide gas, which stretches the sticky gluten and raises the dough. By marking the height in glasses you measure how sugar and salt change the speed of rising.
Salt and sugar as preservatives: pickling cut vegetables
High concentrations of salt or sugar draw water out of microbes by osmosis, so they cannot grow and food keeps longer. You compare how well cut carrot or raw mango keeps with salt, sugar, both or nothing over two weeks.
At what milk temperature does curd set best?
Curd forms when lactic acid bacteria grow in warm milk and turn lactose into lactic acid, which sets the milk proteins. You test milk at different temperatures to find the range in which the bacteria work best.
How fast does milk sour: fridge, shade, sun and boiled
Milk sours because bacteria grow and make lactic acid, and their speed depends on temperature and whether the milk was boiled. Smell, pH strips and curdling on heating show how quickly each sample spoils.
Balloon biogas digesters: kitchen waste against cow dung slurry
Microbes break down organic waste without air and release biogas, mostly methane and carbon dioxide. Measuring balloon size over days compares how much gas different feedstocks give.
Compost heap temperature log: heat from living microbes
Microbes breaking down garden waste release heat, so a compost heap warms up. A daily log of temperature shows the stages of composting and the effect of turning and moisture.
Hydroponic mint and spinach grown in a cut bottle with no soil
Plants can grow with their roots in nutrient water instead of soil. A bottle hydroponic setup shows that roots need water, nutrients and air, not soil itself.
Fenugreek in nutrient water against garden soil: a growth race
Comparing hydroponic and soil growth under the same light shows what soil adds and what plants really need. Measuring height, root length and mass gives data to judge each method.
Cotton wick self-watering planter: how long can a plant go unwatered?
A wick moves water from a reservoir into the soil by capillary action. A plant in a wick pot stays healthy while a normal pot dries out, which shows how to save water and look after plants during holidays.
Salty irrigation water: how much salt can seeds tolerate?
Salt in irrigation water stops seeds from taking up water. Germination counts across different salt strengths show why saline groundwater harms crops.
Compost, vermicompost and plain soil: which grows beans best?
Organic manures add nutrients and improve the soil. Growing the same bean in plain soil, compost and vermicompost shows the effect of each on growth.
Neem, garlic and soap sprays compared on leaf-eating damage
Natural sprays can reduce insect damage on crops without strong pesticides. Counting damaged leaves on sprayed and unsprayed plants gives data on which home-made spray works best.
Ant repellents compared: turmeric, chalk, clove powder and vinegar line
Ants follow chemical trails and avoid some household substances. Counting how many ants cross a line of each substance gives a safe test of natural repellents.
Class seed bank of local varieties with germination record cards
Saving seeds of local vegetables, pulses and flowers keeps variety alive. A record card for each seed packet teaches how farmers collect, dry, label, store and test seeds.
Seed age and storage method: how germination falls with time
Seeds lose the ability to sprout over time, and storage conditions change how fast. Testing old and new seeds kept in different ways shows how to store seed for the next season.
Protecting stored pulses from weevils with neem, ash and turmeric
Grain stores lose food to weevils and beetles. Comparing traditional protectants in sealed jars shows how farmers can protect stored pulses without chemical sprays.
Earthworm food choice chamber: what do vermicompost worms prefer?
A choice chamber lets worms pick between foods. The amount eaten of each food shows what to feed a vermicompost bin and what to avoid.
Thali balance survey: what food groups does a class eat at lunch?
A balanced meal has foods from several groups: cereals, pulses, vegetables, fruit, and milk products. A survey of lunch boxes shows which groups most students eat and which they miss.
Pulse rate and recovery time after skipping, plotted on a graph
The heart beats faster during exercise to supply more oxygen to muscles. After stopping, the pulse falls back to its resting rate, and the time it takes is a simple sign of how the body recovers.
Breaths per minute at rest, after stairs and after a short run
Breathing rate increases with activity because the body needs to take in more oxygen and release more carbon dioxide. Counting breaths gives a simple measure of this change.
School bag weight and standing posture: a photo and tape-measure survey
Heavy bags can change the way a student stands, with the head and shoulders leaning forward. Measuring bag weight as a share of body weight and checking posture in side photos gives data to discuss a safe bag load.
Sleep diary and morning reaction time across a school week
Reaction time is how quickly we respond to a signal. Comparing the hours slept with the ruler-drop reaction distance each morning tests a common belief about sleep and alertness with your own data.
Does washing longer remove more? A 5, 10 and 20 second hand-wash test
Soap helps to lift dirt and oily grime off the skin, and rubbing for longer removes more of it. A harmless coloured powder stands in for germs so that you can see how much is removed in a given time.
Hidden sugar in cold drinks shown as spoonfuls on the table
Many drinks carry a lot of sugar. By converting the grams on the label into teaspoons of sugar, you can see in a vivid way how much sugar is in a glass.
Reading food labels: comparing three biscuits per 100 g
Packaged foods list energy, fat, sugar, protein and salt on the label. Comparing foods fairly means using the per 100 g column and not the per pack figure, which depends on pack size.
Class water diary: how much do students drink on a hot school day?
Water is lost through sweat, breath and urine, and has to be replaced by drinking and by the water in food. A diary of how much students drink shows the range between individuals and how heat affects it.
Eggshell tooth test: which drinks stain and soften it overnight?
An eggshell is made of calcium carbonate like tooth enamel is mostly calcium minerals. Soaking shells in different drinks shows which ones stain and which ones soften the shell, a model for why teeth need care.
Salt in snack packets: a bar chart from sodium on the labels
Labels list sodium, not salt. Converting sodium in milligrams to salt in grams shows how quickly everyday snacks add up. This helps students read the label as a piece of data.
Pupil size in bright and dim light, measured with a mirror and ruler
The pupil gets smaller in bright light and larger in dim light, an automatic reflex that protects the eye and helps it see. A mirror and a ruler let you measure this change without any special equipment.
One-leg balance time with eyes open, eyes closed and a moving floor
Balance uses signals from the eyes, the inner ear, and the muscles and joints. Taking away the vision signal makes balancing much harder, which shows how the senses work together.
Lung capacity measured by water displacement in a marked bottle
One deep breath out pushes an equal volume of water out of an upside-down bottle, so the volume of water displaced is the lung capacity of that breath. It shows that capacity varies with height, age and fitness.
Phone camera drop lens: stomata on a leaf and life in pond water
A water drop or a clear gel bead stuck on a phone camera lens turns the phone into a microscope, enough to photograph stomata on a leaf peel and tiny organisms in pond water. It shows the pores that let a leaf breathe and the unseen life of a pond.
Bile model: how liver juice breaks oil into tiny droplets
Oil and water do not mix, but a drop of detergent makes oil spread into tiny droplets. Bile salts in the small intestine do the same job to fat, so that enzymes can work on it faster.