I am the parent of a 15-year-old HS sophomore, who was diagnosed at age 11 and has been on the pump for several years. From time to time, when he takes an exam, he experiences a high blood sugar, which may be related to stress, among other factors. (He isn't more nervous than other kids about tests, but it is a pressure situation.) There have been times when he feels "off" before or at the beginning of an exam, tests his blood sugar, finds he is high, and asks to be excused from the exam so he can take it later in the day when his blood sugar is under control. It doesn't happen regularly, but it does occur, and his teachers have generally been understanding and cooperative. He doesn't have any sort of 504 plan or its equivalent regarding any of his courses or activities at school. The school knows of his condition, as do his academic advisor and his teachers and the school nurse (who keeps extra supplies and a glucagon kit in her office).
Today a situation occurred where he did not test his blood sugar before starting a science exam (he should do this, but ...), and was not able to finish the exam -- meaning time ran out and he hadn't finished. When he got to his next class, he tested at over 300. When I spoke to him after school on his cell phone, he told me about the situation, and I suggested he email his teacher at once explaining that he was very high during the exam, and asking if he could have a reasonable amount of additional time to complete the test. (My son was still at school, but the teacher had already left school by the time I spoke to my son.) He was not excited about sending the email, but I believe he will.
I would be interested in hearing from other parents about how they deal with this sort of thing. Thanks.