I buy the foam core boards online from Dollar Tree. You get 25 boards, so I order 2 boxes. I mark each board off and get 4-- 8 1/2" x 11" and 3 FQ boards from each one, so it's a lot of boards. They are acid free and you have to make sure that is what you are ordering. I have the shipped to the Dollar Tree store and the send me an email when they are at the store. I love having fabrics on the boards and in my book cases. They are sorted by color and theme and put together by collection for some quilts. Makes for easy storage. Much better than in bins because I could never tell what was on the bottom to find something. Works for me...
