I performed this in Madison and at the Philadelphia Fringe Festival.
For eight hours on both occasions, I stood by a wall waiting for passersby to ask me to jump.
These “customers” could ask me to jump any height they wanted–for instance, an eighth of an inch, four feet, etc.–and could get me to make as many jumps as they wished.
I had a marker attached to the top of my head; in order to mark the maximum height of my jump, I would whack my head back against the wall, causing the marker to leave a dot.
I jumped scores of times each day, with varied success as to my ability to replicate the requested heights. Happily, this did not deter most customers from reporting that they were satisfied with their jumping experience.
When You Say Jump, I Say How High (1’05”) is a video excerpt from the Madison version of the performance. The image above is from the Philadelphia performance.