I stumbled upon this idea when another teacher told me about it and I'm amazed. I spent Monday and Tuesday doing research and Wednesday night I made my pen. It looks awesome. With the help of my husband's craftiness (and his need to make it look professional and clean), we came up with our prototype. I will upload a picture here in a bit.
My only problem my momentary switch isn't working. Can the solder from one side touch the other? If not, how is everyone careful not to let them touch? I will get pictures to post when I return from lunch. I think this school teacher did a great job. I am planning to present it to our principal on Monday. We were getting ready to drop $1300 for a smartboard for my classroom.
ETA pictures:
Unlike the other highlighter pen picture posted, with mine, I didn't cut the top off and I drilled two holes in the side of my pen: one larger than the other to stick the momentary switch through and the other (smaller) just large enough to fit the tip of the momentary switch. It worked out nicely.
These are cell phone pics so excuse the quality.


This is the side with the open hole. I need to fill it in.

Top open (I pulled the top off with my husband's leatherman tool)

Top closed.

The top of the highlighter (the part that normally covers the highlighter part) fits back on nicely, too.