Turn valentines into placemats
As kids, my brother and I would take our stacks of valentines from our school parties and turn them into a holiday placemat by arranging them between two sheets of clear contact paper. We did the same thing with our birthday cards. They made cheap and easy placemats, and my parents didn't have to fight with us over throwing away our "special" cards (I wanted to save everything as a child).
My mom actually kept them all, and now my son is eating off of my old Valentines from the '80s!
And this, friends, is why you buy a personal laminating machine.