El Toro, May I suggest that there are several Spanish language schools in Morelia, Michoacan, known for immersion language learning with optional private accommodation. The best one appears to be: http://www.baden-powell.com/home; but also high on the list: http://spanishabroad.com/morelia-spanish-school/
Morelia is a lovely Colonial town in the state of Michoacan, a.k.a., the heart and soul of Mexico. With an emphasis on government sponsored cultural events is indicative of the general level of education.
The information provided in the latter also notes similar affiliated schools in Guadalajara (if he wanted to be located closer to you) as well as numerous other cities and towns. Personally, I would find Guadalajara too overwhelming whereas Morelia is more intimate, walkable and easier to discover.
From those two options your friend could have a look at both websites to get an idea of style and course content.
Of course there are plenty other options he could research simply by Googling "Spanish Schools in Mexico" to have a broader scope.
I trust this may be helpful.