Here’s a fascinating account on how men traditionally learnt to dance Tango in Argentina, the difference between practicas and milongas, and the importance of changing roles by Christine Denniston.
 

By the 1940s, the way in which a young man would learn to dance Tango was surprisingly uniform. When asked how they began to dance, elderly men generally start, “I was 13 years old, and there was this girl…” At this time, most boys would have left school at 11, at the latest, and would have been working for at least two years. So at 13 they were young adults with quite a lot of independence.

The young man who started to notice the attractions of young women had little option but to learn to dance the Tango. He would go to a men only practice dance, or práctica, and, after he had watched for a little while, one of the older men would start to teach him how to dance the woman’s part.

Once he was considered to be good enough at the woman’s part, usually after about nine months, he would be allowed to lead another young man. They would then continue to learn both parts, until one night, one of the more experienced men would tell them to put on a suit on Saturday because they were going to a dance, or milonga. Usually, it took about 3 years to go to a milonga.

Their first dance with a woman would have to be arranged for them. No woman would dance with a young man she had never seen dancing. There were too many good dancers for her to be interested in risking a dance with someone new, so one of her usual partners would ask her as a personal favor to him, to dance with the boy. If it went well, then he could be left to carry on, as the other women would have seen him dance. If it went badly, then he would have to go back to the práctica until he could do better.

The men did not simply go to the práctica to learn to dance; they continued to go to the práctica for a couple of hours each night, four or five nights a week, before they went to the milonga. In fact, it looks like the real dancing was done at the práctica, while milongas were to meet women. Generally, the men in the prácticas followed better than the women in the milongas did. And in a práctica, one could experiment more and take risks. Dancing with a woman, you had to stick to what you could do perfectly, to increase her enjoyment of the dance.

Abrazo,

Nati & Bruno

Source: http://www.history-of-tango.com/learn-to-dance.html