🚀 go-pugleaf

The golf ball is harder than the rest of the balls you used.  It will
cause the floor to deform more than the rest of the balls in the
experiment.  The wooded floor when deformed is considerable less elastic
than the golf ball so the deformation of the floor causes a larger loss of
energy.  You'd probably get a similiar result with dropping a glass marble
on the wooden floor then comparing that drop with a drop on a smooth hard
floor like torazzo(is that spelling right?) or marble-like floor.
I do a gee-whiz lab similiar to yours and have the students predict how
many bounces the ball will make before it effectively(bounce less than .2
cm) stops and have them actually count the bounces.
That's my $0.02
Larry