My translation

Shuiquan village is a poor, backwards place, the school is run down, and doesn’t even have a clock to tell when to start or finish class, they can only rely on the sun to judge the time. When the sun light hits the nails in the post in the middle of the classroom, the children know it should be time to finish class.
Suiquan’s teacher Gao is going to return home to look after his seriously ill mother. The head of the village has found a replacement teacher who had only attended primary school called Wei Minzhi to take over his classes for 1 month. When Gao saw Wei Minzhi is only 14 years old, he didn’t want Wei Minzhi to do it. The village head said, finding such a person wasn’t easy, and they would have to make do with her for 1 month.
Shuiquan primary school originally had 30 or 40 students, but every year students left because their families were poor, and now there was only 28 students left. Before he left Gao repeatedly told Wei Minzhi she must keep an eye on the students, one less was not acceptable.
Ten year old Zhang Huike was extremely naughty, he didn’t acknowledge that Wei Minzhi, who was not much older than him was the teacher, and only after being pushed by the head of the village to did he reluctantly call her teacher Wei. Because his family were in debt Huike had no choice but to go the city to work part time, and got separated from his fellow villagers at the train station. Wei Minzhi remembered what Gao said to her before he left, and decided to go and find Huike and bring him back. She set out alone on the road into the city and started to look to look for him among the sea of people. After many difficulties she finally met a kind hearted person who worked at a TV station and was eager to help. She went on television and appealed to Huike: Zhang Huike, where are you? You are worrying me to death….come back with me. Huike who was wandering the streets destitute and alone saw the program and couldn’t help but cry……The big reunion made people very happy. Many kind hearted people from the community extended a helping hand, and Huike returned to school. The head of the village said they would use the donations to build a new school.

Excellent!

打工 just means to work/be employed. It can be either part-time or full-time, depending upon the context. In China, a villager like Zhang Huike is hardly likely go to the city to work PART-TIME. 

My translation

Shuiquan village is a poor, backwards place, the school is run down, and doesn’t even have a clock to tell when to start or finish class, they can only rely on the sun to judge the time. When the sun light hits the nails in the post in the middle of the classroom, the children know it should be time to finish class.

Suiquan’s teacher Gao is going to return home to look after his seriously ill mother. The head of the village has found a replacement teacher who had only attended primary school called Wei Minzhi to take over his classes for 1 month. When Gao saw Wei Minzhi is only 14 years old, he didn’t want Wei Minzhi to do it. The village head said, finding such a person wasn’t easy, and they would have to make do with her for 1 month.

Shuiquan primary school originally had 30 or 40 students, but every year students left because their families were poor, and now there was only 28 students left. Before he left Gao repeatedly told Wei Minzhi she must keep an eye on the students, one less was not acceptable.

Ten year old Zhang Huike was extremely naughty, he didn’t acknowledge that Wei Minzhi, who was not much older than him was the teacher, and only after being pushed by the head of the village to did he reluctantly call her teacher Wei. Because his family were in debt Huike had no choice but to go the city to work part time, and got separated from his fellow villagers at the train station. Wei Minzhi remembered what Gao said to her before he left, and decided to go and find Huike and bring him back. She set out alone on the road into the city and started to look to look for him among the sea of people. After many difficulties she finally met a kind hearted person who worked at a TV station and was eager to help. She went on television and appealed to Huike: Zhang Huike, where are you? You are worrying me to death….come back with me. Huike who was wandering the streets destitute and alone saw the program and couldn’t help but cry……The big reunion made people very happy. Many kind hearted people from the community extended a helping hand, and Huike returned to school. The head of the village said they would use the donations to build a new school.