If you loved the LEGO “book” Contraptions, you’ll also like 
LEGO Chain Reactions a new kit from Klutz.
Along with 33 pieces, you get 10 fun projects all with step-by-step directions. Each project, disguised as a LEGO construction, is a physics project for the your budding LEGO engineer.
At $22, this is a perfect gift for the 8-11 set and makes for a good traveling present as well since the included paper ramps, tubes and flags, are all die-cut and ready to go right out of the box with nothing else required other than a flat and steady surface. The kit also includes 6 balls and string. This all makes for a fun dad/son/daughter experience.
Highly recommended!