March is a long time away, but the fundraiser is an ideal opportunity! Being part of a group immediately cuts down on the anxiety he might associate with shaving his head.
Here's an idea: talk to him about participating and offer the suggestion that he raise money by offering to stay shaved one additional day for every so much money he raises, e.g., $5 buys a day. This does two things: it raises money and lengthens the time he stays sly. If he raises enough to stay sly for a couple weeks, there's a good chance he'll grow accustomed to it. Then during his sly time, see if you can arrange a professional barber shave for him to experience. The treatment might seal the deal!
Now you have six months to gently persuade him that sly is the way to go! Good luck!
