Lego's website has a ton of fun activities for kids.  I went looking for coloring pages, which they have, but also found printables such as dot to dot pages, and posters.  They have a list of ideas for a Lego birthday party that looks very helpful.  You can watch movies, and play lots of different games.  And of course you can find a list of Lego products, with product ratings from consumers, too.  One word of advice: there is a LOT of content on this website, and it takes some time to wade through it all because it doesn't have the best user interface.