Though I don't claim to have all the answers and I'm sure there are others out there that have a better system than what I do...I promised a 'request and dedication' blog, so here it is...this ones for you Betsy T. :)
When the kids come home from school we go through their backpack to see what homework they have and what papers have come home. Worksheets and other random papers get put in one pile (my throw away stack), homework that needs to be done in another and excellent test papers, art projects, other memorable papers get put in another stack. The throw away stack is put in the...drum roll please...trash.
Memorable papers/tests are put on this magnet board which is on the wall to the side of my fridge (I have issues with things on my fridge, it looks cluttered right in the middle of my kitchen and yes, I'm just weird like that) -- thank you honey for making me 2 magnet boards for my wall!
Some special notes, report cards, etc. go straight into these boxes I purchased (at Walmart for about $4/each) some memorable things from the magnet board get put into these boxes...some, like the above adorable reindeer will meet it's demise after awhile and head to the trash. At the end of the school year I sort the boxes again and toss some of the things that I changed my mind on and don't need to be kept, the rest goes in a folder and gets put in our filing cabinet.
If the kids want to keep anything (really, Alayna is the only one that cares) that doesn't fit on the kid magnet board (because they brought home A LOT of projects) or things that should meet their demise, but she's just not ready to part with it...then she can bring it upstairs and put it on her own magnet board. She's a pretty organized little girl and every so often she cleans off her magnet board all on her own.
I hope that helps! It might sound like a lot, but honestly, it's about 5 minutes a day because the key is having the kid bins and the magnet board in close vicinity to where you go through their backpacks. I go through them in the kitchen, my magnet boards are in the kitchen and the kid bins are right off the kitchen in my laundry room. It's a quick sort, and all is put away!!