By Jonna Jasmin GüvenI was pumping out the air from a vacuum tupperware box that had a marshmallow inside. The kids' smiles were widening as the marshmallow was expanding inside the box. ‘In fact, you would need to attach a small car to the lid to be able to pull it off’, I added. Now came my favourite part of the demonstration: releasing the air back into the box through a small hole on the lid. I told the kids to take a close look at the swollen marshmallow before I let the air back in.