K'Nex are kid's construction sets from the USA that include Roller Coaster kits that have motorised cars!
The rods and connectors that make up K'Nex kits allow for more mechanical or engineering based designs and inspire modelling and design skills in kids, with the basic kit starting at ages 5+.
If LEGO is not matching the creative needs of your young engineer - consider K'Nex next :-)
Crayons! Specialising in fun, creative and educational toys, gifts, technology and activities for children in Australia.