A non-commercial site for people who like to roll up their sleeves and make fun, mysterious toys and projects that entice scientific investigation. It is a resource for inspired parents, kids, teachers, teenagers, home schoolers and science fair participants. (5/15/2007)
This is one of my favorites websites, it explains how to make toys; science toys.
All science toys and projects on that website are accessible (so cheap to make that nobody is excluded because of cost, and they don't require special skills, tools, materials, or work facilities beyond a kitchen.
Also, that page have a "more about" page with explanations, related activities and high quality links for further research.
It does have clear step by step directions with lots of pictures. They have been thoroughly tested to work, yet also have the potential to be improved by creative inventors and tinkerers. Most project instructions have been improved by helpful feedback from people like you, and some projects are entirely the work of guest authors.
Here is a list of the project listed on that website:
You can find a "science toy video preview" where you can see and hear the finished science toy in action.
This website inspires me (and brings back my childhood) to create new science projects, Sciencetoymaker.org is one of the best of the best on the internet!