2x03 The 101% Solution
First Aired: May. 13, 2014 on CBBC
Summary: Mitchell must pass the "Hardest Maths Assignment Ever". He cheats and ends up earning the mythical grade of 101%, breaking maths, and the world as we know it in the process. The kids' only hope in fixing this is a boy genius who was frozen years ago and has not been properly defrosted.