A new national survey suggests that school principals give high ratings to the former military personnel who come to teach in their schools through the federal Troops to Teachers program.

Since its inception in 1994, the $15-million-a-year program has helped an estimated 8,000 former military personnel to enter teaching. But just a handful of studies have explored the classroom effectiveness of this new pool of teachers.

The survey draws on responses from 875 principals and 1,...