Suggestions:
We had an exciting school trip last week. It started from (on) Monday and finished on Friday. We went to a big farm town by bus. The bus ride was never boring because we talked and laughed all the way. (all the way there or on the way)
When we got there, we were really surprised to find that farming could be so amazing. We saw many old tools and different kinds of fruit and vegetables. We also met some hard-working farmers. Some of them even became our teachers and gave us interesting lessons. We cooked delicious food by ourselves. Some boys were so good at cooking while some lazy girls just waited to eat. On Thursday evening, we had a talent show around a big fire. It was so crazy. We sang, danced and played the erhu. The temperature went down but we didn’t feel cold at all.
However, some of the students didn’t behave nicely. They didn’t wear the school uniform to show they are special. But in fact they are stupid because when they break the school rules, they are noted by the teachers more easily. They said dirty words and threw rubbish everywhere. They talked loudly when others were sleeping at night. They really left a bad impression to on the beautiful town.
All in all, it was a nice trip.
Some of your phrases are unusual but the grammar works.