Correct. If he's limited to transistors and basic LRC components, then the typical hello world would be an oscillator into an output. An LED will blink but I

Correct. If he's limited to transistors and basic LRC components, then the typical hello world would be an oscillator into an output. An LED will blink but I think a piezo speaker is funner if you have a turnpot. When you get to opAmps, add a simple microphone (a microphone element can be had for about 5 cents) and feedback to make one of the classic "shushing" devices.