Can a Public High School Threaten students with remedial cles?

My school is about to start standardized tests (Dakota Step) and our principal came into our cl threatened us with remedial cles on weekends and summer if we don't do above average on them, no matter what our GPA. Is this even possible because these tests don't have an effect on our grade but they could hold us back a year if we don't do above average. FYI im a Junior