Friv.com has a simple UI that’s fairly kid safe. Just throw /old at the end of the URL to get the better, older UI. The new one is kinda meh. Friv doesn’t have a lot of games, but enough to keep you entertained for a while every now and then. Its’ biggest strength was always the simple UI. No accounts, comments, ratings, anything. Only games.

I love that Ruffle exists, it makes so many of these good old flash games sites great again!