Meaning:
“小镇” means “small town,” “错题” means “wrong answers,” and “集” means “a collection.” This term is derived from another Chinese catchphrase “小镇做题家” (xiǎozhèn zuòtí jiā, translated as “small-town expert test-taker”). Unlike these top students who get enrolled in the best Chinese universities, the nickname “a small-town collection of wrong answers” is given to those from rural areas or small towns who haven’t succeeded in acquiring a good education and therefore would most probably end up working as blue-collar workers and struggle to make a living.
Example:
A: 你表弟找到工作了吗？
Nǐ biǎodì zhǎodào gōngzuò le ma？
Have your cousin found a job?
B: 他在建筑工地打工。他父母辛苦工作供他读书，可惜他只是小镇错题集。
Tā zài jiànzhù gōngdì dǎgōng。 Tā fùmǔ xīnkǔ gōngzuò gòng tā dúshū， kěxī tā zhǐshì xiǎozhèn cuòtí jí。
He’s now working at a construction site. His parents worked hard to provide for his education, but he was not succeed in school and could only find a low-paying blue-collar job.