I know the feeling - I dealt with this just last year. The best thing to do is try to showcase some of your work. They don't need or want an entire prompt script because they know what a rehearsal report looks like after the first one, they won't need to see 30.
What I did was get a 1.5" binder with around 12 tabs. Each tab I labeled with "Excerpts from.." and had one for Blocking, Calling, Reports, Schedules, Cast Information, Scenic, Lighting, Sound, Deck, etc.
Within each tab I took various forms, from each of the shows I've done. For example, I did the Laramie Project two years ago and threw in the 6 page sound cue sheet, and then I threw in some of the calling script from South Pacific, etc. Just show the options. Maybe put it in such an order that you show them how you've learned. I put the newest stuff first and as you flipped back within each section you saw how I had modified things, learned to do things better and they really appreciated that.
If you have any other questions about your portfolio, colleges with SM programs or anything like that PM me, I just went through it and now im a BFA Stage Management major.