David and Lemar also performed on the live showdown. Lemar sang the Beatles classic Yesterday.
Carrie thought his performance was "amazing" but Richard said it was "uninspiring."
Before the vote the final five sang an amazing song, Lullaby, written by the students themselves.
In the latest twist, head Richard announced all four remaining students will sing for survival next Friday.
He reckoned it's just too hard to choose between them for someone to go on probation.