A school bus from the Koshkonong School District flipped over in a ditch after running off Highway 99 north of Thomasville and hitting several trees.
17 students and four others were on board.
One student sufferd moderate injuries and the other passengers all have minor injuries.
Most of the injured were taken by private vehicles to Ozarks Healthcare in West Plains.
Emergency crews transported one student to Baxter Regional Medical Center in Mountain Home, Arkansas.
The bus driver was not injured.