Which Aztec school was mainly for sons of nobles?

The Aztec school mainly intended for sons of nobles was the calmecac. It provided intensive education for elite boys during the Late Postclassic period, preparing them for religious, military, administrative, judicial, and political careers.

Students studied subjects including history, religious doctrine, ethics, law, astronomy, calendars, formal speech, poetry, and ritual songs. The calmecac was therefore more than a military academy or priestly school: it helped train the people who would administer temples, government, diplomacy, and the empire’s institutions. Formal military preparation also formed part of the curriculum.

The usual comparison is with the telpochcalli, the “house of youth,” where young commoner men generally received practical training, especially in warfare and civic duties. The division was not completely rigid. Historical sources indicate that some commoners could enter a calmecac, particularly when being prepared for priestly service, while some noble youths could attend a telpochcalli. Even so, calmecac is the canonical answer because it was primarily associated with the education of the pipiltin, the hereditary noble class.

The calmecac in Tenochtitlan stood in the ceremonial center near the Templo Mayor.