ungraded

Researchers also assigned the blocks that fell within the ungraded regions “X.”

Then she took four “ungraded” courses that didn’t use them.

But they also admit to worries about the effect on learning as classes are canceled, labs suspended and assignments left ungraded.

An ungraded card, on the other hand, could always be a 10 to an untrained eye.

The U grade, meaning "ungraded", remains the same.