Statistics and Probability · Probability
Test the birthday paradox
Calculate and test the chance that two people in a group share a birthday.
- Easy
- 1–3 hours
- Free
606 projects · 13 streams · every class
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33 projects
Physics · Optics
Measure the speed of light with a chocolate bar
Find the wavelength of microwaves from melt spots on chocolate, then calculate the speed of light.
- Easy
- 1–3 hours
- Under 250
Chemistry + Nutrition and Food
Measure the vitamin C in fruit juices
Titrate juices with iodine and starch to compare how much vitamin C each contains.
- Intermediate
- 1 day
- Under 250
Physics · Optics
Measure the refractive index of water with a laser pointer
Trace a laser beam entering water at several angles and get the refractive index from Snell's law.
- Intermediate
- 1–3 hours
- Under 250
Statistics and Probability · Probability
Estimate pi by dropping needles
Drop sticks on ruled paper, count how many cross a line and get an estimate of pi.
- Easy
- 1–3 hours
- Free
Biology · Cell Biology
Observe osmosis in potato strips
Soak potato strips in salt solutions and find the concentration at which they neither gain nor lose mass.
- Easy
- 1 day
- Under 250
Physics · Waves
Measure the speed of sound with two phones
Use two phones with an acoustic stopwatch app to time a clap over a known distance.
- Easy
- 1–3 hours
- Free
Physics · Current Electricity
Verify Ohm's law and find where it fails
Plot current against voltage for a resistor and a bulb and explain the difference.
- Easy
- 1–3 hours
- Under 250
Physics · Oscillations
Find g with a simple pendulum and a phone
Time pendulums of different lengths and get the acceleration due to gravity from a straight-line graph.
- Easy
- 1–3 hours
- Under 250
Astronomy and Space + Pure Mathematics
Measure the Earth's circumference like Eratosthenes
Measure a stick's shadow at local noon in two cities and calculate the size of the Earth.
- Intermediate
- 1 day
- Free
Physics · Optics
Build a spectroscope from a CD and analyse light sources
Split light with a CD and compare the spectra of the Sun, LEDs, CFLs and flames.
- Easy
- 1 day
- Under 250
Applied Mathematics + Physics
Derive and test the formula for a pendulum by dimensional analysis
Predict how period depends on length using only units, then confirm the power law with a log-log graph.
- Intermediate
- 1 day
- Under 250
Chemistry · Thermochemistry
Measure the heat released when salts dissolve
Dissolve different salts in water and classify each as heating or cooling the water.
- Intermediate
- 1–3 hours
- Under 250
Communication · Interpersonal
Study how rumours change as they spread
Pass a short story along a chain of ten people and track what is lost, added and changed.
- Easy
- 1 day
- Free
Chemistry · Analytical Chemistry
Estimate the calcium carbonate in eggshells
React eggshell with vinegar, measure the mass of carbon dioxide lost and calculate its purity.
- Intermediate
- 1 day
- Under 250
Biology · Botany
Investigate transpiration with a simple potometer
Build a potometer from tubing and measure how wind, light and humidity change water uptake.
- Intermediate
- 1 day
- Under 250
Software Development · Frontend
Build a pomodoro timer app
Make a 25-minute focus timer with breaks, sounds and a count of sessions done.
- Beginner
- 1 day
- Free
Psychology · Organizational Psychology
Study teamwork with a building challenge
Give teams 18 minutes to build the tallest tower from spaghetti and tape, and observe what the best teams do.
- Easy
- 1 day
- Under 250
Chemistry · Medicinal Chemistry
Compare how well antacids neutralise acid
Find which antacid tablet neutralises the most acid per tablet and per rupee.
- Intermediate
- 1 day
- Under 250
Biology · Evolution
Model natural selection with coloured beads
Play predator on beads scattered on patterned cloth and watch the population shift over generations.
- Easy
- 1–3 hours
- Under 250
Physics + Astronomy and Space
Estimate the Sun's power with a can of water
Measure how fast sunlight heats blackened water and estimate the solar constant.
- Intermediate
- 1 day
- Under 250
Biology · Molecular Biology
Investigate the effect of temperature on enzyme activity
Measure how fast potato catalase breaks down hydrogen peroxide at different temperatures.
- Intermediate
- 1 day
- Under 250
Astronomy and Space + Photography, Film and Animation
Photograph star trails and find the celestial pole
Take a long exposure of the night sky and measure the Earth's rotation from the arcs.
- Intermediate
- 1 day
- Free
Nutrition and Food + Chemistry
Test foods for adulteration at home
Use simple official home tests to check milk, turmeric, honey and tea for common adulterants.
- Easy
- 1 day
- Under 250
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