I recently came across codingame and codewars. I haven't had much time to explore yet, but they look like they'd be helpful with learning by doing. I'm not so great in a classroom type setting. I enjoy jumping in and hands on. But I also have a hard time thinking up my own (useful) projects to use or create for practicing and I'm nowhere near good enough to contribute to something that's open. Anyone use these or have similar favorites? I'm not necessarily a beginner in my languages of choice, but I am rather rusty.