Instruct: Classify Amazon reviews into positive or negative sentiment
Query: Difficult for parents, impossible for child

I bought this for my 4 yr old grandson and I am very, very disappointed in this item. The parts are very difficult for an adult to assemble and virtually impossible for a child to enjoy alone. The box did not contain any instructions to help in the management of the activity. By the time an adult gets any of the parts together so the child can see the gears interact, any child will have lost interest.