This would require SSL interception, which requires a custom certificate on the end device.
If your kid can figure out how to install a custom certificate on their device and MITM SSL to evade filters, (a) you never secured the device (b) you already lost long ago and (c) let’s get that kid a job or a scholarship.
how many of those of us reading this right now would have been able to do this? how many of us reading this right now had parents that would had a clue about any of this to question it?