Hey Lamarque! I am not sure if Ailola Buenos Aries is a good fit for your friend or not. They have classes in the morning, ending at 1PM. In the afternoons, you can schedule private tutoring.
My class only had five students. I was the only Ex-Pat in the class, the rest were students from the USA and Europe in their mid-twenties. There were some other Ex-Pats and older students in the other morning classes.
The school is in the Palacio Barolo on Avenida de Mayo. I am not sure if that is a good location for you and your friend, or not. It was very convenient for me and easy to explain to drivers.
The teachers were friendly, helpful, and never hit my knuckles with a ruler. They just wished they could. I am sure your friend would enjoy the school, if it were in your area of the city.