Smaller rabbits do seem to be able to jump higher than large rabbits. However, the really small rabbit might not be able to jump as high as a rabbit that is about 4-6 pounds.
The smaller breeds are lighter and so don't have as much weight to carry around and jump with. A thinner person is more agile than a heavier person and a slightly shorter person might be a bit more agile that a taller person.
Some of it does depend on the individaul rabbit and how motivated they are to jump or run.
In agility, the rabbits that are about 4-6 pounds seem to be the fastest and highest jumpers. There are a few that are a bit bigger to smaller that also do well. The really big ones do have some trouble jumping higher an getting themselves over the higher jumps. Body type may also play a role as some breeds hold themselves more up than others.
As far s how high, there are rabbits who will jump a 4ft pen easily. The current record for high jump is 1 meter. The Long jump record is 3 meters (about 10ft).
Don't underestimate the little guys. Penelope would look at the high jump for a while and just pop over like it was nothing.