Family, class, pack, bouquet, pair..
What verb goes with them – singular or a plural ?
The answer is – it can be both.
They take a singular verb when the entity acts together and a plural verb when the individuals composing the entity act individually.
The following examples demonstrate this principle:
The team is painting a mural. (The team collectively paints the mural, so the verb is singular.)
The team are in disagreement about how to paint the mural. (The people on the team disagree with one another, so the verb is plural.)
The family takes a trip to California once a year. (The family collectively takes a trip, so the verb is singular.)
The family have differing ideas about the annual trip. (The individuals in the family have differing ideas, so the verb is plural.)