Age for division play is determined as of 12:00 midnight on December 31 in the year prior to the baseball season. (Rule 4). Division ages are as follows:

5 and 6 years T-Ball
7 and 8 years Tadpole
9 and 10 years Mosquito
11 and 12 years Pee Wee
13 and 14 years Bantam
15, 16 and 17 years Midget

T-BALL: This format is designed to get young people interested in the game of baseball by stressing and maintaining active participation of all the players; with mandatory and free substitutions in each inning and emphasis placed on teaching the fundamentals of baseball. The ball is hit from a batting tee and the base paths are 50 feet in length. It is recommended that a soft resilient ball is to be used for play in this division. It is further recommended that a minimum of one coach, and a maximum of 2 coaches, while his or her team is playing on defense, be on the playing field to provide guidance and training to their team in the fundamentals of baseball. Regulation games shall be a maximum of 6 innings and a minimum of 4 innings. Other guidelines for T-Ball play may be found in Rule 19.

TADPOLE: The base paths are 50 feet and although Rule 19 suggests that a batting tee may be used in this division, many local associations use pitching machines or coach-pitch formats. Lead offs are not permitted and a regulation game is 7 innings. The recommended outfield fence dimension is 200 feet. Other guidelines for Tadpole play may be found in Rule 19.

MOSQUITO: Pitching is permitted in this division and a pitcher may pitch a maximum of 3 innings in a calendar day and 6 innings in a calendar week (defined in Rule 13 as 12:01 a.m. Monday to 12:00 p.m. (Midnight) the following Sunday). No balks may be called against the pitcher. Lead offs are not permitted. The base paths are 60 feet and the distance between the pitching rubber and home plate is 46 feet. The pitching mound is raised by a gradual slope to a height of 6 inches above the level of the base paths. The recommended outfield fence dimension is 200 feet. A regulation game is 6 innings unless called earlier for a permitted reason, in which case if 4 innings have been completed, or if the home team has scored more runs in three or three and a fraction innings than the visiting team has scored in 4 and a half innings, then the game is complete (as per Rule 14). Other guidelines for play in the Mosquito Division are found in Rule 20.

PEE WEE: Lead offs are permitted and balks may be called against the pitcher in the Pee Wee division. A pitcher may pitch in a maximum of 7 innings in a calendar day and 10 innings in a calendar week. Shoes with metal cleats are not permitted in this division. The base paths are 70 feet and the distance between the pitching rubber and home plate is 48 feet. The recommended dimensions for the outfield fence are 225 to 250 feet. The pitching mound is raised by a gradual slope to a height of 6 inches above the level of the base paths. A regulation game is 7 innings and Rule 14 applies for early termination. Other guidelines for play in the Pee Wee Division are found in Rule 21.
BANTAM : The base paths are 80 feet and the distance between the pitching rubber and home plate is 54 feet. The pitching mound is raised by a gradual slope to a height of 8 inches above the base paths. The recommended dimensions for the outfield fence are 260 to 280 feet. Pitchers may pitch a maximum of 7 innings in a calendar day and 14 innings in a calendar week. Shoes with metal cleats are permitted in the Bantam Division. A regulation game is 7 innings and Rule 14 applies for early termination. Other guidelines for play in the Bantam Division are found in Rule 22.

MIDGET: The playing field for this division is a regulation baseball field with 90 foot base paths and 60 feet 6 inches distance from the rubber to home plate. The recommended dimensions for the outfield fence are 320 to 400 feet. With some minor exceptions for substitutions, teams at this level play according to the regular rules of baseball. A pitcher may pitch a maximum of seven innings plus one, in the event of a tie game, in a calendar day and fourteen innings in a calendar week. A regulation game is 7 innings and Rule 14 applies for early termination. Guidelines for play in the Midget Division are found in Rule 23.