In Harry Potter and the Deathly Hallows (I), a Muggle teacher died.

Charity burbage, first appeared on page 9 of Chapter 1 of Deathly Hallows. The professor who teaches Muggle Studies at Hogwarts School was arrested by death eaters for publishing an article in daily prophet defending Muggles and encouraging wizards to learn Muggle knowledge, and finally died under Voldemort's Abada death curse. Harry read about her in the newspaper.