I agree the quizzes and even the unit tests just add more work onto things, it already takes long enough to find all the information especially for some concepts like fractions. They work for early math but then it starts to get harder and takes longer to do your research on stuff and necessary to start making your own notes on it all. The KA website regularly changes things too that puts your unit score down so i wouldn't bother about it.

So that's why i just gave up on doing them and only focus on the getting the practise questions to proficient, i think that's a good enough mastery system and the quizzes and unit tests are meant to appeal to schools but it just stops working soon enough because of how much is actually involved in all the stuff you really need to know in mathematics which isn't how little schools teach and now how little are in the units there's more you gotta know.

They could take the quizzes, unit tests, and mastery challenges out and instead adjust the leveling a bit with the practise tests where the top level is "Mastered", i find since we can do the practise questions as many times as we want to that the leveling adjusts well to how much you really know and tell you if you're not practised enough because when you get even just a few wrong it puts your level down.

More focus needs to be put on putting a few more variations of practise questions in them including what happens to numbers that are a bit bigger than just smaller 1 digit or 2 digit numbers, so that everyone using KA knows that it's not as easy as it seems when the numbers start to get bigger.