I use the long skinny poster frames and hang them sideways on the wall. You can put 4-5 pieces of regular size paper art pieces in the frame. I am also lucky enough not to live in my daycare home so my DH put giant sheets (8'x4') of Homasote (corkboard material) on the walls. I have tons of things hung on them using staples. I have one sheet hung on at least two walls per room. One board is for art work, one has shapes and letters, one is for our Star of the Month, one is in entryway for announcements and notes for parents and one is for whatever theme bulletin board collection we feel like displaying. You can paint the homasote whatever color you want and when there gets to be too many holes from tacks and staple in it, you just repaint it. They are awesome! Here's a link if anyone is interested in what homasote is:
http://www.hstech.org/howto/material/homosote.htm