The Santa Cruz Beach Boardwalk is a state historic landmark with roots going back to 1865. The wheelchair friendly area is filled with carnival games, rides, and an arcade. No need to wait in lines for any ride since they are not accessible (to our benefit). There is also tons of junk food to eat and beer to drink, including Santa Cruz's classic candy shop Marini's featuring salt water taffy. It certainly is a tourist hot spot so to avoid crowds, I recommend week-days.
When looking at the ocean, on the right side of Santa Cruz Boardwalk there is an accessible wooden ramp (above photos) that travels far out onto the sand. Near by is a lifeguard stand where you can get a beach wheelchair (shown below). Also, on the other side of the Municipal Wharf, near the Boardwalk, is another wheelchair accessible beach walkway made out of rubber (shown below).