When I recently went back to Cool Math Games to feel nostalgic, I played a few Papa’s games without any problems. As long as you have up-to-date browsers and security software, the site itself is safe and doesn’t contain any malware. Being careful is always a good idea, but these games shouldn’t hurt your computer.

https://www.reddit.com/r/Virushelp/comments/1bvhg5j/is_cool_math_game_safe_for_kids/