The twin boys from next door loved Discovery Toys Marble Works, but it was starting to loose their interest. Thought I would "upgrade" to what looks like a very cool toy, adding gears and a "power lifter" to the "marble experience" and so i bought "Marble Mania"
It comes with about 25 different types of "parts" that all friction fit together. The manual is okay, but could really use a bigger format to make reading / reference easier. It took me about 5 very frustrating hours to assemble this monster. Hint: group the similar parts together and make sure you have the right piece...because if you don't you will have to take it all apart and start over. Also, the manual only illustrates the "pictured" construct...some alternatives that require different levels of understanding and demonstration of gear ratios and other "capabilities" would really enhance the learning "possibilities / fun".
Anyway, the base does not completely interlock and will only stay together if mounted on a tabletop or hard surface. This makes moving the toy very problematic. Hint: get a piece of wood plank and cut to size to provide a permanent base for the toy. This is not something you assemble, take apart and put away...just too complicated and time consuming to re-assemble.
The friction fit allows for quite a bit of "play" in the alignment of the various gears and slides and must be constantly adjusted to keep the gears and marbles running as planned. The unit only comes with 3 marbles...for $50, they could provide a bag full.
Still, the motorized "power lifter" is cool (if very slow) and the marble runs are pretty interesting, once you get the alignment of the supporting framework perfect. It held the boys interest for about 20 minutes...pretty long for these two. They are too little to experiment with alternative configurations which would probably be a lot of fun for a pre-teen.
I think this toy would be excellent if your child has the patience, skills and interest in creative problem solving required to assemble the structure. Children who could go beyond the pictured construct and build "experimental models" with these parts would have a lot of possibilities to explore.
Don't plan on a young child building this on their own or being able to use it unsupervised.