Not the OP, but here's half a dozen off the top of my head:
* WiFi mesh
* Cellular/LTE
* Satellite internet
* LoRa
* Bluetooth
* Ham radio sending data packets
* Walkie-talky voice communication with a few friends outside the school (probably not what the OP meant by "wireless network" but I think it's technically correct ;)
In Brazil there's been a fairly sophisticated scheme based on that. It proceeded more or less as follows:
1) the "service provider" hired some highly specialized "candidates" who would enroll for the exam and take it
2) these fake-candidates would then quickly solve the questions, focusing only the few subject matters they were specialized in. One is usually not allowed to leave the exam room carrying the printed materials, unless they accept to wait for a specified amount of time (1 hour before the final time or so, IIRC). But these guys were able to memorize the answers and, then, simply left.
3) after leaving the room, the fake-candidates would meet a team in a car nearby. They had a radio transmitter there, and started to broadcast the answers.
4) the cheaters who hired the "service" would carry a radio receiver with a tiny earpiece implanted under their skins. They would then listen to the answers and write them down
I don't remember how did they find that out. I believe it happened when an exam proctor suspected about a candidate answering the questions too quickly.
What are the dozen ways?