JONESBOROUGH, Tenn. -

Students injured in a Washington County, Tenn. school bus crash are slowly going back to school.

The student most critically hurt returned to David Crockett High School Monday to visit with her friends.

Cheyenne Bunton stopped by the school during lunch. Doctors say she cannot return to classes this year.

School officials say several other seriously hurt students have also been coming by to visit with friends.

The number of students still out of school is shrinking. "After this week, it will be four maybe five," says principal Andy Hare. "There are several with doctor's appointments this week to get clearance to come back; we are providing homebound services."

The investigation into what caused the bus to run off the road and flip is still ongoing. The highway patrol says the final report could be complete by Wednesday.