Imagine a mini computer with a cardboard case running a very bare distribution of GNU/Linux stored in a 4GB micro SD card. It comes with a cable that has an HDMI connector on one end and on the other is an HDMI/RCA combo connector. The machine has two USB ports where you connect a keyboard and a mouse. It has a wifi chip and an ethernet port for internet connectivity. It comes with 512MB of RAM.
When you turn it on, it loads up a screen to connect to your network. When you're done configuring or if it has already been configured before, you then arrive to a TTY. You're auto logged in as a generic OS user, but you typed in
/join class0123 student9876 to attend your class. The computer will poll a server until a live video feed comes online. You see your teacher on the screen and there's still a TTY below the video. The teacher starts the class, and interaction from the students are done via the TTY while the teacher responds over live video.
The teacher enables "quiz mode" where teacher asks questions in real-time and all TTY interactions are considered quiz answers. Since exact answers are expected from the teacher's multiple choice questions, you get instant feedback per question if you're right or wrong.
The teacher discusses some final pointers, but you're almost late in your next class so you type
/leave. You join the next class. And the next one, then the next one. Your done with your classes and you type
/shutdown to call it a day.
Ideal cost of the total setup is $25.