Fun to build, fun to play with!
I’ve been thinking about this concept for a couple of years before I got down to actually build it. Here is the result:

This is an infinitely reconfigurable marble run game. OK, not infinitely – but I checked the math, and there are more permutations possible than there are grains of sand on all of planet Earth’s beaches. So we’re good.
Any marble run is fun – there is something oddly satisfying in looking at rolling marbles – but this game does so much more…

The track board is made of square tiles, which one can assemble in those countless ways. Most of the ways fail to lead the marbles to the bottom, but others do; finding the configurations that do so, and do it in various interesting ways, is half the fun. And the challenge… because there is the constraint that the wooden tiles come in ten different types, each with a carefully chosen number of copies, so you can run out of a tile you need all too often. It’s a puzzle, really, both logical and physical. And it can be played as a single player, collaborative multi-player, or competitive two-player game. I’ve tested it in all three modes on kids (and some adults) and a good time was had by one and all!
I give a demonstration, along with some comments on the woodworking methods I used, in this video:
Incidentally, all the raw material was once a bed that somebody threw out… and now it’s a cool game instead. That’s the power of woodworking for you!
This is a wonderful idea for a family woodworking project. And to be a thinking game for players, kids will gain from each engagement. I picture building and playing with my own grandchildren. Thank you for sharing!