This is actually a chid's-size go-kart bodied to resemble the GM Monza SS, one of a pair of Corvair-based show cars from the mid-1960's. The coupe was called the Monza GT, and the roadster the Monza SS. As I kid I saw one of these displayed at a local Chevy dealer, and I honestly believe I would have killed for it!
These were built for Chevrolet as promotional tools, they used to do Corvette-based ones in the early 60's. Those were called "Corvette Jr.'s" so I suppose these were "Monza SS Jr's" or something like that.