Why would you direct new comers attention to eval'esque functionality? They should stay far far away from it. Come to think of it, everyone should stay away from eval functionality!
Agreed. In my class I always start with the hard/wrong way. Point out why it's hard/wrong. Let them hate it. Then show the easy/correct way. You can't just point them at something and say, "Do it this way or else." That's not teaching. That's directing.
I feel like you could start with manually calling the function, and then introduce callbacks as a way to get your code to run in response to some event. A callback is no different to a regular function after all.
If your way works, then it works though I suppose.
Once they do, you show the problems with it and show why callbacks are better.
When it comes to pedagogy, I'll use every trick I can.
And I always win.