Building Sets 

Blocks
Wooden ABC Blocks	Brio Wooden Blocks	Maxi Building Blocks	Jumbo Foam Blocks	Pattern Blocks

Building Kits
Gears	Magnetix	K'Nex	Erector Sets	Zometool

LEGOs
Jumbo Legos	Lego Creator Kit	Star Wars	Bionicle	Mindstorms

building sets 
Educational Toys
Nerd Toys
Science Toys