A few days before the AP test, my AP Chemistry teacher said he was going to have bagels for us during the break they give you during the test. His reason was he thought that was better for you than donuts.

Another student met privately with him and made a very persuasive argument that bagels were a horrible idea. Not only were they worse than donuts, they would have a negative effect on out test taking ability during the second portion of the test.

The teacher was convinced, and we had donuts instead of bagels.