Here’s a site where parents take an active role when it comes to their children access to videos in the Internet. It’s powered by Youtube and the videos at Totlol are safe for kids under 13. Parents submit to Totlol videos found at Youtube that they consider appropiate for children and share them in the Totlol community.
There’s no need to register if you just want to watch videos. Since this is a portal based on Youtube filtered videos, you can find that searching within certain criteria returns no results, but it’s worth a visit to pick some nice clips from Sesame Street or other classics.