I had a student exemption before the draft lottery. I remember being very concerned about no longer being "protected" by the student exemption and I considered my options. Getting a reasonably high enough number put an end to my concerns and tentative planning. Volunteering was not an option under consideration.
I thought about my former high school classmates who weren’t so lucky with the lottery and who might end up in a body bag. I had lost contact with all but a few classmates by then and I still don’t know who didn’t make it back in one piece.