Homestarrunner* at a glance may seem dumb, but the more you view it the more you realize it is genuinely funny. There are no real problems, unless you find "lady"ing and the use of crap offending. From time to time, there are a few problems, such as the consumption of "'old ones", (AKA some sort of beverage, possibly alcoholic). All in all, if you watch it with them, any kid 9 or older can watch the toons on this site. Just be sure to talk about it afterwards, such as how making fun of people in real life isn't funny. If they are teens however, they should probably be okay without you watching it with them. But that does not mean you shouldn't, for it is pretty funny, and even elderly people may enjoy it.