When Uromastyx climb walls it is often referred to as "Glass Dancing". Everytime they do so, I pick them up and hold them and interact with them for awhile then put them back and they stop. I think it's just their way of saying "HEY YOU! I want to get picked up to come out and play" since they can't talk or vocalize anything.
Try that with your juvi leo and maybe he/she will stop. It works for me when my leo does it.
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1.1 mali uro's-Ares and Apollo
1.saharan uro- Iris
1.2 bearded dragon-Hades and Draco
0.2 leo gecko-Kalypso
0.3 tokaye gecko-Sid Vicious
1.0 tarantula-Peter Parker
0.2 dog-cheeka
0.2 zebra finch-beeps
0.2 african gray parrot-keya
1.0 red headed parrot-pancho
0.3 Fish (sorry no names for them)
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