[.ca] Sunshine Makes the Seasons (Reillustrated) (ISBN 0060592036)

Explains why we have seasons:
if you have an energetic child like my 5 year old who is always asking why - this is a great book. I got this book around summer soltice when my sun did not understand why he is going to bed when it is so bright outside. By doing the "experiment" with an orange and a flashlight, I think he understands why we have seasons.