LELAND, Ill. (AP) — Parents of students at a northern Illinois elementary school are angry after an older student led an experiment that asked their children to open child-proof medicine bottles.

Parents weren’t told in advance about Friday’s project at Leland Elementary School.

The principal and the Leland School District superintendent sent parents a letter on Sunday saying that a junior high school student worked with kindergarten and first grade students “to gather data for a science fair project.” The letter says the older student “at points” demonstrated how to open the containers.

Superintendent Jodi Moore told the Chicago Tribune that the older student wasn’t acting maliciously.

Parents are upset the project could happen without their consent and are concerned about the school’s communication methods.