From https://www.namobuddha.org/monasteries.html

Thrangu Tashi Choling, located close to and facing the Great Stupa of Boudhanath, was founded by Thrangu Rinpoche in 1979 when construction began. The ancient stupa is a major pilgrimage site for Buddhists, one of the most important holy places in Nepal. Boudhanath is the largest Tibetan settlement in Nepal and is also the largest Tibetan settlement outside Tibet.
At the time of purchasing the land, there were only a few monasteries in Boudhanath, and the area surrounding the Stupa was mostly rice fields. Rinpoche was just getting established in Nepal and had very little money. The original plan was to build a small monastery. Later it became necessary to expand to accommodate the many monks who continuously came to join the monastery.

There are many monks under the age of eighteen and most of these boys are from rural areas of Nepal, particularly the mountain areas bordering Tibet. Some come from Tibet, India, and Bhutan. In the monastery they study and practice Buddhism, philosophy, rituals, and reading and writing Tibetan as well as English. From an early age they learn to develop the good habits and discipline that will serve them and others throughout their lives.