On the tall hills, he sleds down 2 tall hills * 4 times per tall hill = <<2*4=8>>8 times.
He sleds down the small hills half as often so he sleds down each hill 4 times per tall hill / 2 = <<4/2=2>>2 times per small hill.
On the small hills, he sleds down 3 small hills * 2 times per small hill = <<3*2=6>>6 times.
So in total, Wilson sled down the hills 8 times on tall hills + 6 times on small hills = <<8+6=14>>14 times.
#### 14