Regular, kid-pitch little league. A few small tweaks for
this age group (e.g., 4 outfielders). 46 foot mound with
60 foot bases.
Major league style baseball (aka "Bronco" rules), including leadoffs and balks. Only
three outfielders and no restrictions on stealing bases (no straight steals of home). Fifty foot mound with 70 foot bases.
Taking leads, pick-offs, and - usually - curve balls. 54 foot mound. 80 foot bases.