Question

should there be a comma before the highlighted word?
whenever kristoff wears pajamas to school, his teacher lets him nap during class.
keep the comma
remove the comma

Explanation:

The sentence starts with a dependent adverbial clause ("Whenever Kristoff wears pajamas to school") that comes before the independent main clause ("his teacher lets him nap during class"). A comma is required after an introductory dependent clause to separate it from the independent clause.

Answer:

Keep the Comma