"Teacher Wu can't teach at all!" Wu Shunxing, a substitute teacher for the third grade at Ping'an Elementary School, looked at the group of little troublemakers in front of him, feeling a surge of frustration. He, a promising graduate in pharmaceuticals, bravely took on the role of substitute teacher, only to realize it was the beginning of torment...

“巫老师都不会教书的！”平安小学三年级的代课老师巫顺兴看着面前的一班小魔头，血气上涌。他，前途光明的药剂系毕业生，不畏挑战接下了代课老师的担子，却不知那是折磨的开始……小朋友的质疑、校长的训话、家长的刁难和要求、最后莫名其妙背的黑锅……这一切，没有教书经验的菜鸟老师要怎么见招拆招呢？