With three young children (all under 7 yrs old), I've got a beef with just about every existing website targeted to them. They are all so chock-full of ads and links that my children can never do much until veering off to some page where they don't know what happened. Usually it's because they clicked on a Google ad, some other ad, a registration link, a link to buy something, etc. They cannot browse the web even on "safe" sites without constant supervision to get them un-stuck.
I also realized there are lots of good animal wildlife and other educational videos on sites like Google Video, YouTube, etc. It would be great if the kids could watch them, but those videos are mixed in with everything else which is entirely unsuitable for them. Given that I'm working on TagTooga.com which has great feed capabilities, I decided to create a kid's video site: KidSafeVideo.com which takes live feeds from TagTooga.com of videos I've selected from Google Video. I tested it on my kids today, and they love it. I could really see something like this in a classroom, with video on topics from Lions to Volcanos at the teacher's fingertips!
The site is entirely non-profit. There are no ads, and there will never be clickable ads, if any advertising at all. There are no links offsite. It is a very simple site with videos categorized by topic. There are about 50 videos there now, mostly animal oriented, with some funny cartoons as well. Everything is suitable for young children. You might want to check it out to see if your kids like it.
KidSafeVideo.com
PS> Now for the Geek/Technical note. Check out how it's done by viewing the source of a page on kidsafevideo.com. You'll see that the video feeds are coming from a bit of javascript pulling from TagTooga.com.
I can add and delete videos at will from TagTooga.com, and changes are automatically reflected on kidsafevideo.com.