|Photo Credit: In Order for Life|
Memory Box - I have a big plastic box for each of my kids. Any large art that is really special goes in there (along with other sweet memories of their life).
For even more organization, put things in manilla envelopes and label them by age, grade, or type of memory (i.e.cards, pictures, crafts, or whatever other items you would like to keep). These will not only be wonderful for you to look through down the road, but your children will appreciate them once they are passed onto them!