Alan Carr on why he entered the competition
Four celebrites prepare for the ultimate test on this year's Stand Up to Cancer special
Brother and sister go head to head in the finals
Rhea, 10, embarks on the spelling and comprehension round
Joshua is put to the test by his father
Richard Osman hosts the demanding Maths and Memory round
Highly gifted youngsters battle it out to be crowned the UK's brightest child of 2016
There can be only one winner...
It's the semi-final and we're down to the last eight
With two contestants eliminated after each round this week, the stakes are high.