Freggie Tales -  Food fun with Freggie (the 5 to 10 a day mascot)(Canadian)

Kid's Zone  - Lots of fun ways to find out what's good for you (from the USA)
 

Carrot Museum - carrot experiments and trivia

Dole Superkids - Although this is a commercial site, it has great ideas for teachers, parents and kids plus yummy recipes.