Made by Kiwi Crate, but with a STEM-focus on the crafts/projects. Affordable at $19.95/mo. From reviews online, it looks like they send one large project and make recommendations for smaller, less-intensive projects and experiments. It comes with a "zine" with lessons on that month's theme, and instructions and materials for the main project.
I think, there must be a lot of toys and different sets here. That is the reason I bought https://melscience.com/US-en/che... to test it with Caitlin. We tried to use it for a couple of days and will be thankful for any experience from the others.