How to write books for 4-8 year olds?

A while back i discovered a site that lets you publish your own books, this site takes your book and they print copies to order, once a sale is made you get a percentage.

So, i thought i would give it a shot. i have a fairly good imagination and im sure i can tell little kids cool stories because i still remember being a kid like it was yesterday. however, as many of you have no doubt noticed my spelling and grammar are not too good, and on top of this i have no idea how books are supposed to be written, the rules and regulations so to speak.

so, do you have any advice or useful links about writing books in general, and do you have any advice or links about writing for kids?

i already have a fairly good idea of what i would do if i did things with what i know now, but would like to see if i can get some advice to help make the books better.

the general idea for now, is a kid (boy) that likes to mess and round and experiment things, he goes on adventures, gets in trouble and solves the problem and some times learns a moral lesson along th way.

i imagine the books to have big friendly cartoon pictures on each page, with about one paragraph per page in large print.

any help is appreciated, thanks.