I agree with PPs on Legos or maybe K'Nex.
Also popular with that age: Nerf guns and swords
For board games my DS' love/loved Sorry, Sorry Sliders & Uno
They also love:
Playing Cards (war is a favorite game),
Tools - Home depot sells a nice starter set specifically designed for that age group - includes a couple of screw drivers, a wrench, hammer, tape measuer and a pair of pliers - perfect for dissecting those broken toys
any ball that's small enough to fit into a pocket that can be used to bounce off a wall for recess
Small Remote control helicopter or truck
Minecraft game for PC
and last but not least...
BATTERIES!