On the 6th of December 2010, fifteen young people come together to begin a new chapter, in Kamiyama.  From across Japan, with burning hearts guided by the smell of fermenting sudachi, the chance to rediscover themselves and to forge Japan’s future with their bare hands; the Kamiyama Juku, born.
I designed a scientific battery of tests for the students but, unfortunately, I didn’t manage to complete them.  Data wise, the following documents are all I have:

So a quick scan of the data reveals that everyone is either Blood Type A or O.  A and O are the most common blood types in Japan.

Blood type A are, apparently:

“People with blood type A have a deep-rooted strength that helps them stay calm in a crisis when everyone else is panicking. However, they tend to avoid confrontation, and feel very uncomfortable around people. A types are shy and sometimes withdrawn. They seek harmony and are very polite, but all the same feel that they never really fit in with others. A types are very responsible. If there is a job to be done, they prefer to take care of it themselves. These people crave success and are perfectionists. They are also very creative, and the most artistic of all the blood types, most likely because of their sensitivity.
People with blood type A are also likely to be considered classic “type A’s”: stressed and conscientious.  (In anime, people like Hotohori are type A’s.(??))”

Type O, apparently:

“People with blood type O are outgoing, energetic and social. They are the most flexible of the blood types. They easily start up projects but often have trouble following through because they give up easily. They are flighty and not too dependable. O types always say what’s on their mind. They value the opinion of others and like to be the center of attention. Also, people with O blood are extremely self-confident.
Type O, the most “average” blood type, is considered the best type in Japan.”

There are SEVEN females and EIGHT males (and one male tutor).

FEMALES:  Type A = 6       Type O = 1
MALES:  Type A = 4     Type O = 5

So there is a majority of the blood group Type A.  There are more female Type A’s than male Type A’s.  There are more Male Type O’s than female Type O’s.   The tutor is Type O.

Conclusion:

Nihon wa sute-ki ga takai.