For projects like this, a great local history resource is a book called "The History of Chelmsford," written by Wilson Waters in 1917. Being as old as it is, it covers in great detail what Chelmsford was like in the 18th and 19th centuries.
It is also a large book, which often intimidate kids (and adults), but it has a tremendous amount of useful information. In this case, it even has a chapter called "The Life of Long Ago," which went a long way towards answering the student's question.
However, within this chapter, there is a subsection called "Social Life." As I was skimming it, I started to laugh. The full text of this book is very graciously provided online, but there were a few paragraphs on practical jokes (noted as "a common amusement") I thought worth pulling out:
A man, after spending an evening at the tavern, might, with difficulty, get into his chaise in the dark, and find his horse apparently backing when told to go forward, some wicked boys having hitched him into the thills with his head where his tail ought to be.
On a cold winter night the boys stuffed the schoolhouse chimney with hay, and poured water down upon it, which froze solid, so that it was impossible to have a fire the next morning.
The first thing a new schoolmaster had to do was to show himself master of the biggest boys, which, sometimes, required a knock-down blow, resulting in universal respect for the school-master. In such a tussle, one poor man had his long hair rubbed full of burrs.
Parson Bridge, when courting his second wife, the Widow Abbott, in taking a short cut to her house, "the Ark," had to cross a plank over the brook. One evening it broke, and let him into the water, the boys having sawed it nearly in two in the middle.
Ah, those old tyme Chelmsfordians knew how to live.