But all the teachers agreed Kwame Kwei-Armah's performance of Ain't No Sunshine was - in Carrie's words - "Soulful, stagy - a class above the rest."
She even reckoned he could make records professionally!
Meanwhile Will Mellor tried very hard indeed with Robbie William's hit Let Me Entertain you - but didn't get too much praise from Kevin the dance coach.
He reckoned Will didn't make it light-hearted or smiley enough.
Comediennes Jo Brand, Ruby Wax and Doon Mackichan all held back their nerves. But you could still tell they are more used to making people laugh!
Now it's up to the public to decide who they like best.
At 10.35pm, the two students with the least votes will have their future decided by the others.
One has to go - who will it be?!
We are CBBC's official Celeb Fame Academy website, so make sure you check back for all the latest goss updated every day!
And you can watch the celebs in action at 8am on BBC Two, 5.20pm on BBC One and 5.45pm on the CBBC digital channel.