Here is a short info about it. It is magical and the most well organized one.
The Ulugh Beg Madrasa (Uzbek: Ulugʻbek madrasasi) is a madrasa (Islamic school) in the historic center of Samarkand, a UNESCO World Heritage Site in Uzbekistan.[1] Together with other monuments, it forms the monumental ensemble of Registan, the old heart of the city.[2] It was built between 1417 and 1421 by the then-Timurid governor of Samarkand, Ulugh Beg, Timur's grandson and prominent astronomer, who was later emperor between 1447 and 1449.
It definately a must see monument.
Samarkand itself is a beautiful city with a deep history. It's interesting to walk around it, but it's better with a guide or a knowledgeable person, because everything is in the details. Ulugbek is an educator of Islam, researcher and scientist, creator of madrasah schools to promote education to the general population. They were in great demand and not everyone had the opportunity to study at a madrasa. I recommend it for a mandatory visit, because the indescribable spiritual atmosphere and inner sense of history in such places will definitely not leave anyone indifferent.