For the price and educational value this is an excellent product. The main drawback is that there are a ton of little screws and I don't think there's any way a child under 12 could get them all in alone. That's a tall order even for an adult. I put it together with 3 children ages 4, 6, & 9, and it held all of their interest to varying degrees, but I had to do 90% or more of the assembly b/c the screws are so small and it was tough for them to keep a hold of and tighten the screws. There were a few assembly issues along the way, but figuring out those issues and getting everything working is part of the fun of a project like this and everyone was very pleased with the final result.