They are in the middle of holiday study camp! Amano and Hayase go back to second grade level to improve their math abilities to get trough the U of T entrance exam.
Amano upsets because he felt they are being made fun of, but he finally understands the reason that arithmetic and math are necessary for U of T test and also, for surviving in their life.
Then, a legendary mathematics teacher, Tetsunosuke Yanagi, who was very popular in the previous series, appears. He starts training them with the same old his Spartan way of teaching....