9 experiments found
Clear filtersEnergy flows from producers through consumers in a food chain; only about a tenth of the energy passes to each next level
Build a food chain from organisms found around a Nepali paddy field, place each at its feeding level, and follow how energy is lost at every step.
Decomposers such as bacteria and fungi break down dead organic matter fastest when it is warm and moist; plastic is not biodegradable
Leave fruit peel, leaves, paper and plastic in sealed jars of soil, change the moisture and temperature, and measure how much decomposes over four weeks.
The Sun drives the water cycle of evaporation, condensation and precipitation
Shine a lamp on water in a covered tank with ice on the lid. Watch evaporation, condensation and rain happen in a small model of the water cycle.
Weather records of the highest and lowest temperatures and the rainfall, averaged over many years, describe a place's climate; the mean temperature is (highest + lowest) ÷ 2 and the range is highest − lowest
Read the weather records of Delhi, Mumbai, Kolkata, Dhaka, Kathmandu and Chennai in January, May and July: the highest and lowest temperatures, the daily range, the mean and the rainfall. Compare the cool winter, the hot dry summer and the wet monsoon.
Electricity and fuel cost money and resources, and making them often pollutes the air; small habits, such as switching off, using LED bulbs and covering pots, save energy, while leaving things on or open wastes it
Look at twelve everyday habits, from switching off lights and cooking with a lid to leaving the TV on standby. Find out why each one saves or wastes energy, and sort them.
1 mm of rain on 1 m² of roof is 1 litre of water, so a roof collects area × rain × 0.8 litres (some splashes or soaks away): even a small roof can store a lot of water in the monsoon
Choose the size of a roof and the rain in a month, and work out how many litres of rainwater a family could collect in a tank, and for how many days it would give a family of five their water.
Trees take carbon dioxide from the air by photosynthesis and store the carbon in their wood: a grown tree takes about 21 kg of CO₂ a year, while a car gives out about 0.17 kg every kilometre
Plant 1, 10 or 100 trees and let them grow for 1 to 20 years. Find how much carbon dioxide they take from the air, and how many kilometres a car could drive to give out the same amount.
Burning petrol and diesel gives carbon dioxide, a greenhouse gas: kg of CO₂ = km travelled × kg per km per person, so walking or cycling gives none, a shared bus gives little, and a car gives the most for each student
Choose how you get to school, how far it is, and for how many days. See how many kilograms of carbon dioxide the trips put into the air, and how many trees it would take a year to soak it up.
The Earth turns 360° in 24 hours, so 15° of longitude is 1 hour: places to the east see the sun first and their clocks are ahead; each country sets its standard time from a longitude near its middle
It is noon in Kathmandu. What time is it in London, Delhi, Tokyo or New York? Pick two cities and see how the turning Earth gives every country its own clock time, and why Nepal is 5 hours 45 minutes ahead of London.