If a student has access to a resource room or special education classroom during the day, IEP spelling goals can be taught there. Usually children with moderate to severe disorders are working on sight words or phonics.
What to do in the general education setting?
Have a copy of the list. The student simply copies the words.
Choose 5 or more words, depending on the student, that he should learn to read by memory. On test day, put those words in a word box at the top of the page. The student has to identify the word and write it on the appropriate line. For attention reasons, the paper should be numbered according to his words. For example, if the student memorized words 3, 7, 8, 10, and 12, then his paper should be numbered accordingly. If you mix up the words on the test, his paper may look like 2, 5, 6, 8, 11.
This works best for students who also have a physical handicap with the cognitive impairment. Choose 5 or more words, depending on the student, that she should learn to read by memory. On test day, list the words that she memorized. When she hears the word, she identifies it from the list and writes a number by the word. Teacher says, #4 is "language". The student would write the #4 by that word on her list.
These options give the student access to and exposes her to age appropriate instruction.