The child, 4, allegedly picked up rocks and threw them on the ground.
The child's teacher than told other students to throw rocks at the boy to teach him a lesson.
About six students are seen hurling rocks at the boy, who is on his knees and crying.
The officer who saw the video said: "I observed approximately 6 toddlers throwing rocks at a white male toddler.
"The toddler is kneed down covering his face crying.
"A background voice says, 'He'll learn to stop, ok that's enough'."
The teacher who allegedly egged on the students to hurl rocks has been interviewed by police.
So far, no arrests have been made.