On one of my giveaways, I asked folks to comment with their favorite children's math book. Someone suggested The Dragon's Scales, a Step Into Reading Level 3 (Grades 1-3*) book. I wasn't familiar with it. After reading it with my kids, I've found it so cute that I'm having a hard time returning it to the library! It's now on my wish list.
Summary: When a dragon threatens to disrupt the life of the townspeople, a little girl challenges the scaly creature to a math contest involving knowledge of weight.
The girl outwits the dragon through questions like, "Which weighs more, one apple or two peas?" and "Which weighs more, a little bag of gold or a big bag of cotton?" The dragon always goes for the obvious...large things or multiple things must always be heavier. After she beats him in the contest, the girl teaches the dragon, asking him which weighs more, "a bucket of bricks or a bucket of feathers?" At first the dragon starts to say that they must be the same since they're in identical buckets. After a long, hard, dragon-think--and with the help of the girl--he decides that the bricks must weigh more. And the town gets its own "watchdragon."
It would be fun to follow this up by having kids compare a variety of objects with a balance bucket, asking questions like "which weighs more...10 pennies or 10 dimes? 25 cottonballs or 5 buttons?"
*Although this is a Grade 1-3 book because of it's early reader designation, it also seems ideally suited to preK-K children who are ready to explore weight.