Public schools increasingly talk a good game about the healthy stuff they’re serving for lunch. But the meals don’t always match the menu, as Zachary Maxwell discovered as a fourth grader. Maxwell sneakily recorded the gross lunches at his school, and from that footage was born his aptly titled documentary, Yuck.

Getting this footage wasn’t easy, he told The New York Times:

Reader support makes our work possible. Donate today to keep our site free. All donations DOUBLED!

His hidden-camera documentary was almost derailed last year when he was caught filming without permission by a fearsome enforcer — the lunchroom monitor in his school cafeteria.

“She sent me to my teacher, and my teacher told me to delete everything,” said Zachary, who is now 11.

Grist thanks its sponsors. Become one.

Zachary pretended to delete the day’s shots. After that lapse in production security, he said, “I fired my lookouts.”

But it was worth it: He proved to his parents that the food the school was promising — dishes like lasagna rolls and roasted spinach — weren’t what he was being served (grilled cheese). And the film’s been winning all kinds of accolades. If you live in New York, you can catch it this June at the Manhattan Film Festival.