As you may know from reading about the Jigsaw Puzzle, I am a contractor of KidsLoop in South Korea. There’s an internal “proof of concept” for putting a physics engine (matter.js) into an H5P content type. You can see brief demo in the video below. If you have any thoughts about the “seesaw” content type, feel free to let KidsLoop and me know. If this turns into something useful, I am sure that there’ll be an openly sourced version, too, just like there was an openly sourced version of Jigsaw Puzzle.