1. They are a wonderful gift.
=> What a wonderful gift they are!
2. They are a good team.
=> What a good team they are!
3. They are a very clever class.
=>What a clever class they are!
[Are they all grammatical? Would you check them?]
1 answer
2 and 3 are okay, but 1 needs to be phrased in the singular. Give it a try!