That was quick! I posted my comment on your page this morning, and I thought that it would take long for you to reply. I was just working on my other project - the climate education curriculum - and having just learnt about the 'discussion' page, I thought to just check in case someone has left a message for me. I guess many of the workshop participants are busy bees this weekend (for us on the other side of the Deadline)!
I can imagine your sons experiences with electron configuration. It's an abstract concept. I also struggled learning it at high school and at university. It only started to make sense to me when I started teaching it at high school. And I think that because all my students are visual learners (i.e. struggled to understand abstract ideas that are explained in English), they appeared to understand better when a diagram is drawn.
Thanks for dropping by. I'll come around and leave a message in your Talk page.