Peel a clementine or an orange. Light a candle and let it burn a little. Take a piece of the peel and squeeze the yellow on the peel against the flame of the heating light.
What can you see? Which fruit creates the most fireworks?
Explanation
It is not only air in an orange peel, but there are also oils in the peel that you use when, for example. makes perfume. When you squeeze the peel against the flame, you release the oils in the shell that are ignited by the flame.
The idea comes from Louise Alfredsson at Nätraby School in Nätraby via www.lektion.se

An experiment that contains both science and practical mathematics. Alex counted for 137 nails that stuck to the magnet and could certainly have counted longer if the nails in the box had not run out. Can all magnets hold the same number of things, or does it differ, and if so, why? Something to look into!
nade till 137 spikar som satt fast på magneten och hade säkert kunnat räkna längre om inte spikarna i lådan hade tagit slut. Kan alla magneter hålla lika många saker, eller skiljer det sig, och i så fall varför? Något att undersöka!