I stumbled across this little puzzle site, Confusion, last night and I’ve been working through the first trails over my morning coffee. The site is arranged with five collections of puzzles that need to be solved to collect keys and access the final set, which is the most difficult. They are mostly rebuses, riddles, and other “tricky” puzzles, and they definitely get harder as the path progresses, though you’ll probably recognize many of them if you’re a puzzle enthusiast. I haven’t finished the site yet (just starting Metal World), but it seems very kid friendly – I’d have loved it when I was thirteen or so. And you can request hints if you need them, though I don’t know how prompt the feedback is (it’s not clear if it’s automated or not).