These context clues worksheets on the nouns salutation and valediction might be useful at most schools to introduce these two concepts–useful for understanding forms of correspondence–to your students. You could also use them as they are, or rewrite them, to introduce the words salutatorian and valedictorian to your graduating seniors.
If you find typos in these documents, I would appreciate a notification. And, as always, if you find this material useful in your practice, I would be grateful to hear what you think of it. I seek your peer review.