Gum

Gum was a consumable from the planet At Attin, an isolated Jewel of the Old Republic.

Gum came in various colors, including red, yellow, green, and blue. Rather than being swallowed, it was spat out after chewing, forming a pliable substance. In the New Republic Era, unruly younglings from At Attin Middle School Gamma were notorious for sticking chewed gum to the head of RX-01 who piloted the tram that delivered the students to school, ignoring the droid's appeals to stop bullying him.

Text and facts from the “Gum” article on Wookieepedia, licensed under CC BY-SA 3.0. Modified for this site.