The boys admitted to knocking over the headstones for fun, he told WISH-TV.
Truitt led a project a few years ago to fix and document the headstones and clean up the cemetery in the Boone County town of some 1,500 people about 30 miles northwest of Indianapolis. He said more than 100 soldiers are buried there.
"Seeing the damage that's been done, and the disrespect that's there is really hard. It does make you angry," Truitt said. "But I don't know how you get angry at a 6-year-old, a kindergarten kid. We'll accept this, and hopefully everybody learns a lesson."
A town police officer has sent a report to the county juvenile department to decide what punishment the children might face.
Truitt said repairing the damage cost between $40,000 and $75,000.