I don’t think I’ve ever seen an ad for FunBrain but they have been around since 1997 and are one of the best sites for safe, educational games and videos for kids.
Their target audience is pre-k through grade 8. The site is free to use although it pays for itself via ads. The ads are not very intrusive, but do promote products like Lucky Charms and Froot Loops etc. I would have tagged this site as appropriate for younger kids, but it’s too easy for little ones to inadvertently click an ad and then not know how to get back to the site, so I recommend the site for kids who are at least 6.
The site offers games, reading, and videos.
Many of the games seem to use HTML5 rather than Flash, which means they should run on any device, in just about any browser.
The reading section has full books with scanned pages that a child can read on a tablet or phone or other device.
The video section has a lot of original content not available elsewhere, with puppet characters, cooking shows, music, and more.
All in all, a good, free, safe place to let your kid explore and learn while having fun.