How many prepositional phrases are in this sentence This morning Andrew ran through the hallway so that he could get to his classroom?

Let's break down the sentence to find the prepositional phrases:

* This morning: This is an adverbial phrase, not a prepositional phrase.

* through the hallway: This is a prepositional phrase (preposition: "through," object: "the hallway").

* so that: This is a conjunction, not a prepositional phrase.

* to his classroom: This is a prepositional phrase (preposition: "to," object: "his classroom").

Therefore, there are two prepositional phrases in the sentence.