Violent deaths in schools went up slightly during last year's school year.
A Bureau of Justice statistics survey found that 21 people were killed in the 2004-2005 school year.
But the study also found that four of every one-thousand students said they were a victim of a violent crime.
That is compared with six students in the 2003-2004 academic year.
The study did not include this year's school shootings, like the Amish Schoolhouse shooting in Pennsylvania.