Super Grover's Cable Glide (sometimes called Grover's Cable Glide) was an opening day attraction at Sesame Place in 1980.
Kids would line up on the either side of a valley and would grab on to a zip line. The park employee would then swing them across a 120' valley.
The bottom of the valley was filled with mulch in 1980:
By 1983 the mulch had been replaced with sand.
When the park first opened the single pit accommodated two zip lines and had four employees. The employees were stationed on the platform (one at each end of each zip line.)
Children would line up at either platform.
As the child held the zip line, an employee would run down the ramp pushing the child to the other side. Once the child got to the other side another child was pushed across.
In 1983, the procedure had changed. There was now only one zip line with an employee at each end and one at the bottom of the pit . The employee on the end would push the child forward to the employee in the middle who would send the child the rest of the way with another push.
In October of 1980 a 12 year old girl named Karen broke her wrist falling off the zip line. Perhaps this instigated the changes in setup and the decision to change from mulch to sand.
Super Grover's Cable Glide was located at the edge of the park, in fact, you could see the street from the platform:
The ride was eventually removed as the park expanded.