Most of us don't know very much about slugs and land snails but Christopher Taylor at Catalogue of Organisms is doing his best to educate us (and himself): Wild Slug Chases (Taxon of the Week: Gastrodontoidea).
I need to warn you that his posting isn't suitable for all audiences. Some of these animals are capable of having sex with themselves and that's not something you want your children to know. Also, some of these animals aren't as pretty as warm fuzzy animals like cats. I find it helps to think of snails and slugs as dinner rather than pets.1
1. For some people, this works for cats too.