According to Jim Recap: Trashed
As Jim tries to hang some artwork from Ruby on the refrigerator, he finds that there is no room. So Cheryl has him put it outside in the box with the rest of her stuff. When Jim tries to pull the box down, he's covered with all the other junk up on the shelf, and it's decided that they will rent a storage unit to keep all this crap. But when Jim and Andy get there and find out that it will be $60 per month, and not even Andy's sweet-talking of the lady at the desk can get them a discount, Jim does what any sane person would do - he throws it in the dumpster.
Everything is fine until Cheryl wants to pull some of Ruby's artwork out for a tribute to the art teacher, Mrs. Reifschneider (whose name Jim can't ever remember), who is retiring. Then there is a bit of a problem, because even after they head to the dumpster and try and find it, they can't. They do find a banana, and since it's sealed up, they eat it (it tasted fine). But after Jim and Andy get dumped into the back of a trash truck, they head back to the house and try and come up with another plan. In the end, they only have one option. They recreate things themselves.
At the party for the retiring teacher, Jim proudly shows off Ruby's artwork, and Cheryl gleefully recalls every moment when Ruby made each of them. It's getting to him so badly that Jim can't hold it in any longer. He has to tell her, and he does. He and Andy made every one of them last night! Cheryl is furious, but Ruby is the one who gets mad when she hears that Jim threw her things in the trash.
Strangely, when Jim tells her that it just means she has more room to make more stuff, Ruby is fine - but Cheryl is still mad. So Jim sits her down and explains that while some work is special, it can't all be special, so what if they keep a couple of pieces from each year. That seems to calm Cheryl down nicely, and they can go in and enjoy the rest of the party.
