I took a vacation day off work to be a guest speaker at my son's middle school. I taught several classes of 6th and 7th graders on desktop PC parts and how to build them.
First, I gave a PowerPoint presentation to discuss the various parts and their role/purpose. Then, after a Q&A session, I had enough time to give about half of the class some hands-on training (after school, I showed the teacher how to assemble and disassemble so she could help the other students the next day who didn't get a chance). Using old Dell and HP desktop PCs from the XP and Vista days, I showed them how to remove the heatsink/fan, CPU, motherboard, RAM, and HDD. There was no GPU. Also, for safety reasons, I removed the power supply in advance. After assisting them on how to take it apart, I let them take turns putting it back together.
Other than a couple of students who were obviously bored, majority of them were excited and learned pretty quickly. It was a fun day to teach them something I enjoyed doing.
Them - "hey I need advice on buying a computer"
Me - "sure id be happy to help you pick something out or ill build a great computer for you"
*week later*
Them - "yeah, i just decided to buy a computer from Best Buy"
Me "......................."