Everyone's childhood is different. But there are common objects, sights, sounds, smells, and memories from elementary school that most Gen Xers and Millenials share.
Personally, when i think back to being in elementary school in the '80s, I remember the taste of the chocolate ship cookie we got on Fridays (with the pizza). The humiliation of getting nailed in the back during nation ball. And the grumbling, grinding sound that happened when you slipped a disk into the drive on an Apple IIe computer.