Quizzes
An explainer can end with a quiz: a multiple-choice question on the core idea, with three or four answers and one right. The narration asks it, you answer right on the slide, and it tells you how you did, sometimes with a hint on a wrong answer.
Quizzes are scored per viewer: correct on the first attempt earns gold, second earns silver, third earns bronze, and you can keep trying until it's solved. A later solve still counts, without a medal. It's a ten-second check that you understood the lesson, not an exam.
Getting quiz slides
Quizzes appear in explainers created on scrimba.com/explain when you're there to learn something. For a lesson, asking makes the check more likely: end with a quiz.
Some explainers never get one: a summary or overview, a task on your own code like refactor this function, a page explainer from the Chrome extension, and any lesson in the TLDR teaching style.