I'm an accountant, so of course I'm a math nerd. My wife didn't like the measuring and cutting steps and expressed her frustration with it one day, so I read the directions and started cutting. She decided she liked that arrangement, so I started cutting everything for her. When she signed up for a class, I went to do my part. Both she and the teacher encouraged me to make my own quilt, so I took the class alongside her. Then she realized she had to do her own cutting, and she was less enthusiastic.
Now we work together, shop together (and enable one another), and I have picked up a few vintage machines as a result of reading this board. We do get to spend quality time together in the sewing room, and I think overall she's glad that we can work together on quilting projects. If you want something that you can do together, it's relatively harmless to teach him. You may have to share tools for a period of time, but he will buy his own necessities like scissors, thread snippers, the all-important seam ripper, etc. He may eventually need his own machine, but you can address that when you come to it.
Let us know how it works out.
Darren