I have done a lot of beach jumping in the past (before starting kite-surfing), and it is great fun.
Though, it needs to be done on a place with lots of space + uncrowded, and soft sand is more suitable to avoid ankle/knee injuries on landings. Some people do it on grass...
I use to do it with Mandibule foils, these are 2 lines foils especially design for this purpose: huge hangtime and very slow turning. Only with handles, no harness, it is much safer that way. Also it is wise to do it with someone else, not on your own, because you quickly get tired on your arms/sholders. With kite-surfing kites (bar and harness) it is more dangerous because you can't let go as easily in case of problem and you have more lines to deal with... but can be manageable too.
Pierre Cardineau, the designer of Mandibule kites got the world record for lenght:
see you
Jacques