This volume begins with their journey to Hokkaido for the “Promotion Exams” which decides whether the first year students will be able to proceed to the second year in the academy (Chapter 19).
The Promotion Exams begin but the "rebels" are assigned together in each class to have them expelled by giving them bad ingredients. Before the exam, Erina offers to help them to prepare for the exam by sharing her knowledge in strictest manner. With their knowledge and skills plus Erina’s assistance, will they able to create a high-quality dish with limited ingredients and within the remaining time?
This volume ends with Souma needs to face off with one of the members of the Elite Ten and the assigned ingredient will be something unexpected and new for Souma.
Nothing outstanding in this volume. Every volume has similar style - new challenge, new character or old character returns for the challenge, the main character able to deal with every challenge. I will still continue reading the story and hope something unexpected happens.
More reviews can be found on Goodreads: Food Wars!, Vol. 21: Shokugeki no Soma (Food Wars: Shokugeki no Soma #21).