@caraplayingstuff Sure, there are RF detectors that will detect a cell phone's signal, as long as it's not turned off or in airplane mode.
There are also some phone apps that claim to detect other devices, like tracker apps, airtags, and other cell phones. I can't say how well they work as I haven't used them.
But your main problem is going to be limiting detection to a specific area, unless you plan to blanket the entire school, also catching faculty in the net.
Can you implement a no phones in the class policy, where you simply collect all cell phones at the start of class, or require that they be left in lockers?
