We are the proud owners of an Imaginarium Deluxe Marble Race. Tonight, my boys (and the girl, although not directly) asked me to help them build a big Marble Race,following the plans in the instructions.
We built it and as we were doing it, Benjamin pointed out things that he thought wouldn't work. But we kept building. When it was done, we tested it - and a few things didn't work right. They were the ones he mentioned during construction.
He then told me that if we reversed two pieces in the middle, the whole thing would function. We carefully isolated the pieces and reversed them - and now it worked perfectly. I have to marvel at his spacial reasoning and mechanical/civil engineering capabilities - I couldn't see the mistake and I wouldn't have been able to fix it.
Here's the marble race...and yes, we keep the marbles themselves up high and watch Ariel when we race them. She likes to put Marbles on the track and we let her do that - supervised. Let me know what you are amazed by with your kids.