1. Frame it! The obvious choice, but sometime it’s too big a hassle, especially when the art is coming in by the bagful at the end of every week. Another option is wall appliqués like Kitsch artwork frames ($36) which make it easy to “frame” art on the wall and change it out depending on your feeling. A few other options like this are available, but make sure the openings are large enough to handle big sizes or you’ll be stuck trying to find only small drawings that will fit (usually rare for the pre-school set). 
2. Use iPhoto or animoto.com to make a musical slideshow you can send around to folks by email.
3. Create a binder (larger than 8X10) to store flat art that you can organize by year. Or, take photos of the art and use services like Apples iPhoto or Inkubook.com to make pro-looking art books featuring your child’s masterpieces.
4. Take a trip down to the local hardware store and get the artwork laminated. Laminated art makes for fine family placemats so everyone can enjoy them.
5. Take photos of the art and make it into a calendar to give away this holiday season. KodakGallery.com and all the other photo sites have calendar options.
Whatever you do, don’t throw it all away OR store it in boxes waiting for some day. The longer it sits unframed, the better chance it will eventually end up at the bottom of a landfill anyway.