Before stamps became stickers, which started in earnest in the United States around 1989, they were printed sheets of paper with water-activated adhesive backing. In 1987, Sesame Street visited the US Postal Service to see how a stamp, specifically the .22 cent puppy dog Love Stamp, was made: A girl visits the postage stamp factory.

Follow this with more Sesame Street classics: I Beam, a drum from a barrel, making apple cider, old paper, new paper, spinning clay on a pottery wheel, and how crayons are made.

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