i clicked your link and got more info as to your dilemma.

if we are just talking about something like a pad of newsprint: rip off the cardboard back, leave it in the class room, and bring a few bulldog clips to keep it all together.

using better paper? well, in my opinion (which is only my opinion) there are so few good quality pads of paper, that you are better off buying a bunch of sheets of good paper and rolling them up. again, you'll need to leave a board at your classroom and clip or tape the paper to it.

as for a rack, i can't think of anything cheap enough. best idea i have might be an xtracycle, but they are certianly not cheap.