I started working in a kitchen two weeks ago and today I was informed that next week I would have to take a written test on my knowledge of the menu. The manager will schedule an exam day for me, where I'll either have to come in early or stay late to complete the test. When I first started working, I was given a binder full of recipes that I assumed were only to be used as a reference, but no, it's literally study material for the exam. In talking to my coworkers it seems that the test results determine the percentage of tips you get, and if you fail the exam then your tips will be negatively impacted. I should note it's a minimum wage job at a somewhat upscale chain restaurant.
Is this at all common practice? Is it normal, or is it an enormous red flag?