The test-out button (in gold, bottom left).

A test-out allowed a user to individually test-out of that skill if they already knew the skill.

Its format was similar to a lesson at that time (having 20 sentences from the skill itself) except the user couldn't peek at words for their definition and/or use a Heart Refill on lost hearts, much like a placement test.

Following the creation of the Crowns system in May 2018, this feature was removed, although there is discussion between the developers of the Crowns system that they would like to re-add it in some shape or form at a later date[1].

The user can still test out to a particular checkpoint if they know all of the skills before that checkpoint.