Gongzhuling is a city in ex-Manchuria, and in Japanese pronunciation Koshurei.http://en.wikipedia.org/wiki/Gongzhuling
IJA established there Rikugun Koshurei Gakko (Army Koshurei School) in Aug 1939. At first it was intended for a combined battle (tank, infantry and artillery) research & education school. But the mission of school gradually changed.
They maintained one infantry regiment, three artillery battery and a tank company, filled by young soldiers. One mission of the school was officers' command training. Newly promoted officers in Kwantung Army practiced there to command a real troop. Another mission was to research vs. Soviet fortification combat. After the Pacific Wae began they must have had newer research topics but I don't know.
In Jun 1944 suddenly they received an order to form 68th brigade with all the troops attached to the school. The 126th regiment was converted from 'exercise 1st regiment (教導第1連隊)'. At first they had only two battalions. In Taiwan, Sep 1944, they received personnel from other divisions (50D, 66D) in Taiwan to form third battalion.