Sunlight arrives with an eight-minute delay.
A short calculation turns an enormous distance into something you can imagine.
Read →Why does an octopus have three hearts?
The memorable number makes more sense when you follow the jobs.
Read →A whale looks like a fish. Why is it a mammal?
Classification asks about more than the shape that moves through water.
Read →The Sun is a star. Brightness is not the reason.
Recognising the source of energy is more useful than judging a dot in the sky.
Read →Helium was spotted in sunlight before it was found on Earth.
How a colour in a spectrum can become evidence for an element.
Read →Summer is a matter of angle, not just distance.
Use opposite seasons to test a tempting explanation of summer and winter.
Read →A puddle can disappear without ever boiling.
Separate evaporation from boiling, then design a small observation of your own.
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