P.K.
IMO a little moving up party is plenty for little ones. I personally do not
believe in the whole cap and gown thing at that age. In the old days, a cap
and gown was saved for high school graduation and when you put it one it
was a special time. If they start in pre school the cap and gown will have
absolutely no meaning. So I would do a party and maybe create little books of special moments in preschool. Have fun.