Why does the Sun disappear?

The new Earthlearningidea for this week is 'Why does the sun disappear? Demonstrate what happens when the Moon hides the Sun.' This activity demonstrates how a small object, which is near, can block out the view of a much larger object that is further away. Do your pupils think that the Sun and the Moon often appear to be the same size in the sky? They are not the same size at all and yet the Moon can block out the Sun completely so that it goes quite dark - - solar eclipse or total eclipse of the Sun.
This is our first activity in the category 'Earth and space'. Can you think of some more? Have a look at the home page on our website - 'Invitation to contribute'. We shall be very pleased to receive your contributions.