Here's why:
* Transitive verbs require a direct object. The verb "hope" can be transitive (e.g., "They hoped for a miracle"). In this case, the verb is followed by something that receives the action of the verb.
* Intransitive verbs do not take a direct object. In the sentence, the verb "hoping" is followed by the clause "it would snow," which is not the object of the verb but rather an idea or a state of being.
Therefore, "The kids were all hoping it would snow" is an intransitive sentence.