Chalkboard

The Chalkboard is an object used for creating a canvas for making either spaceships or drills.

"Space Race"
Steven decided to make a space ship with Greg but it crashes and then Pearl says that their measurements were "off" which leads Greg to say that their measurements "could'nt be off if there were never any" which lead Pearl to use the chalkboard to do a rough draft of what a possible spaceship blueprint would be.

"Back to the Barn"
At the barn, Pearl explains to Peridot that they should first organize all the parts they have in the barn and then draft a blueprint for the drill before they get anything started. Pearl then looks at the chalkboard and tells steven "Ugh... sorry, Steven, it's a lovely drawing but it won't look like this." After a while, They both decided to build robots and Steven then uses it to count the points each of them made as they battle to see which robot is better.

Trivia

 * In total, the chalkboard has made two appearances during its time on the show and both were at the barn.