Renowned Korean history instructor Choi Tae-sung, known as 'Big Star Teacher' with 7 million cumulative students, made his first-ever appearance on the MBC talk show 'Radio Star'. During the 'Teachers' Day Special: Passionate Priests' episode aired on the 13th, he shared behind-the-scenes stories from his tenure as a CSAT (College Scholastic Ability Test) exam review committee member. Choi detailed the intense nature of the position, which involved over a month of extreme isolation, strict communication controls, and the need to keep his whereabouts confidential even from his own family to ensure exam security. | Renowned Korean history instructor Choi Tae-sung, known as 'Big Star Teacher' with 7 million cumulative students, made his first-ever appearance on the MBC talk show 'Radio Star'. During the 'Teachers' Day Special: Passionate Priests' episode aired on the 13th, he shared behind-the-scenes stories from his tenure as a CSAT (College Scholastic Ability Test) exam review committee member. Choi detailed the intense nature of the position, which involved over a month of extreme isolation, strict communication controls, and the need to keep his whereabouts confidential even from his own family to ensure exam security.