Students in Rutherford County were sent home from school on Monday if they failed to provide proof of the required immunizations.
School officials began contacting parents about the immunization requirements last April.
Several letters were sent home to parents and phone calls were made to make sure parents knew about the shot requirements.
All Rutherford County students were given until last Friday to provide proof of the vaccinations.
"As of last Monday, we had 1,100 kids that had not shown proof yet," said James Evans of Rutherford County schools. "We started sending out notices to affected students. This morning we got down to 250 students."
State health officials changed immunization requirements for school children in 2010.
Officials told Nashville's News 2 the new requirements are designed to keep Tennessee children safe.
"I think a lot of times parents now haven't had experiences with these diseases. So I think it's kind of easy to become complacent and kind of forget how important they are," said state epidemiologist Dr. Tim Jones.
Immunization shots are offered at all county health departments.
Click here for more information on required child vaccinations in the state of Tennessee.