I don't know about classes separating teams during the regular season but the girls had one big tournament (16 teams) for 6-player until 1985 when 5-player was adopted for some schools. 5-player became statewide in 1994.
From 1985-1993 there was one 6-man championship (still 16) and one 5-man championship game (just 4 teams, usually big schools until 1989 and then 8 teams) for girls basketball.
In 1981 Norwalk defeated Ankeny for the title.