Comedian Ruby Wax also impressed viewers with her lively songs, regardless of the fact that she can't really sing.
She sung versions of Pink's Get The Party Started and Avril Lavigne's Sk8er Boi.
All of the other students, who were evicted earlier in the week, were there to cheer the pair on.
Dobby
Earlier on, Pop Idol Gareth Gates failed his driving test for Comic Relief, along with loads of other celebs.
And EastEnders star Natalie Cassidy, who plays Sonia, and Big Brother star Jade Goody, failed their tests too.
Viewers were also treated to a spoof Harry Potter sketch, by Dawn French and Jennifer Saunders, who set up a scene called Harry Potter and the Chamber Pot of Azerbaijan.
The sketch featured Basil Brush as Dobby and posh British actor Jeremy Irons, who played Snape.
Celebs and non-celebs are hoping to beat the incredible £55 million raised in 2001.
Africa
All the cash goes to people who need it most in the UK and Africa.
Since Comic Relief began in 1985, £72.4m has been given to projects helping poor and disadvantaged people in the UK.
Another £141.7m has been given to projects in Africa.
Hear story
What are you doing for Comic Relief?
I met the stars at the Comic Relief launch
