Iowa

History
Throughout the history of Iowa, only thrice has the dynasty of Ames Middle School been challenged, in 2011, 2013, and 2014. Every year that Iowa has sent a Division C team to nationals through 2016, it has been Ames High School. This represents one of the longest continuous reigns of any high school team in the nation.

The 2016 Iowa State Science Olympiad Tournament was the first time Ames High School's reign was threatened. Mount Vernon Community High School tied with Ames High School, for the first time in Ames High Science Olympiad history. It was decided that the tie would be decided by the school with the most gold medals. Ames High School narrowly won the state title after edging out Mount Vernon Community High School 8 gold medals to 7 gold medals. In 2017 Mount Vernon defeated Ames High School for the first time, although Ames High School reclaimed the state title the following year.

Past State Champions
This is a record of the past state champions and runners up, and their respective places at the national competition, if applicable. Scores at the state competition may be shown in parentheses.

Competitions
Iowa does not have any regional competitions due to the number of teams in the state, only 31.

Division B

 * Ames Middle School
 * Cedar Falls Middle School
 * Durant Middle School
 * Franklin Middle School
 * Gilbert Middle School Team A and Team B
 * Holmes Junior High School
 * Johnston Middle School Team A, Team B, and Team C
 * McKinley Middle School
 * Miller Middle School
 * Mt. Vernon Middle School Team A and Team B
 * Roosevelt Middle School

Division C

 * Ames High School
 * Burlington High School Team A and Team B
 * CR Washington High School Team A and Team B
 * Dubuque High School
 * Gilbert High School
 * Iowa City West High School Team A and Team B
 * Johnston High School Team A, Team B, and Team C
 * Marshalltown High School
 * Mount Vernon Community High School