I get it, French class
You say this when someone is so dumb they take forever to finally understand something simple, like they're still confused while you're done and ready to die.
You're explaining the difference between je and tu. They say 'I get it, French class' while you're already thinking about lunch.
You're trying to teach them the basics of pronunciation. They say 'I get it, French class' after you've already moved on to the next lesson.
You've been talking about être for 45 minutes. They say 'I get it, French class' while you're still explaining it.