What happens to grade-limited products when a new school year starts?
A product's grades are saved by name (for example, "K" or "3"), so they carry over from one school year to the next. A product limited to 3rd grade will be shown to the parents of next year's 3rd graders once the new school year begins. Duplicating a product also copies its grades to the new copy.
If your school's grades change — for example, you stop offering Pre-K — a grade that no longer exists still appears, checked, on the product's edit page so you can see it and decide whether to uncheck it.