Please keep in mind that there is an extensive set of chapter summaries on eNotes.com. Please note the links below. I am happy to give you a short summary for each chapter in the meantime, however.
In Chapter 1, we meet Nick Allen whose ideas always have interesting results for his elementary school. In third grade, Nick turns his classroom into a tropical paradise. In fourth grade, Nick mimics the sound of a red-winged blackbird. First, he gets his friend Janet in trouble. Then he lets her in on the joke. The two spend the year having fun letting out "peeps" in the middle of class in order to confuse the "hawk," the teacher.
In Chapter 2, Nick enters fifth grade as an unhappy camper. His new teacher, Mrs. Granger, is a big fan of dictionary usage. Nick is not a big fan. Nick gets definitions by context (or by asking his father). Nick is convinced the year isn't going to be fun.
In Chapter 3, Mrs. Granger's class does prove to be a drudgery for Nick. Even worse, Mrs. Granger is on to all of Nick's usual antics (such as tangents to deflect homework) and asks him to do an oral report on dictionaries as a result. Nick is disgusted.
In Chapter 4, Nick begins on his oral report but is distracted by hearing all of the other children able to play outside on this beautiful day. Nick eventually looks up the word "dictionary" in the encyclopedia in hopes to find out something to tell the class about word origins. Nick is about to give up hope on fifth grade fun until he gets an idea about his report.
In Chapter 5, Nick begins his oral report with information about Samuel Johnson and Mrs. Granger is pleased. Fortunately for Nick and for the rest of the class, Nick goes on and on and on about the dictionary. Now Mrs. Granger is not pleased. She cuts Nick off and does her lesson plan in record time and explains how WE create the meaning of words. Then she gives out homework. Mrs. Granger wins.
In Chapter 6, Nick starts to think about how people create word meaning themselves. Nick makes up a new word for the pen and begins calling a pen a "frindle." He even goes to the store and asks for a "frindle," pointing to the pens. The clerk hands Nick his "frindle." Nick and his friends promise to never use the word "pen" again. They have created a new word: frindle.
In Chapter 7, Nick makes sure Mrs. Granger hears the new word when he declares the following:
Mrs. Granger, I forgot my frindle.
The class is on to Nick's plan. No matter what, Nick remains cool and collected as Mrs. Granger gets angry about the change in wording.
In Chapter 8, Nick has a new plan. Everyone holds up a frindle as part of their school picture. Mrs. Granger threatens detention for the use of the word. The class is encouraged and wants to get put in detention. Eventually, Mrs. Granger calls Nick in for a conference. She has him sign the back of an envelope that Nick is not allowed to open until the word "frindle" disappears. The next day hundreds of kids get detention for saying the word.
In Chapter 9, the principal visits Nick and his family at home and asks for respect for authority. Mom sides with Nick. Dad sides with the principal. Nick stands firm and says that "frindle" is not just Nick's word anymore.
In Chapter 10, a newspaper reporter comes to the school to get the scoop. The reporter talks to the principal and asks students in detention their reasoning. Nick, however, refuses to be interviewed. All the reporter receives is a picture of the class with Nick's face circled.
In Chapter 11, the newspaper article comes out and makes the frindle issue sound like a war between teachers and students. Lots of people get angry, even Nick's mom. No one knows who sent the reporter the picture of the circled Nick.
In Chapter 12, kids from other schools start using the word frindle. Local celebrities get on board, too. Everyone is interviewed on the local news. Nick admits that he is not sure what will happen to his word, but that everyone will have a say in it somehow. The local news story goes national and Nick begins receiving money as a share of the profits from frindle merchandise.
In Chapter 13, Nick's dad is happy that everything seems to be simmering down at school. The word has become a normal part of the vocabulary. The only issue is Mrs. Granger's spelling test that always features the word "pen" (that all of the kids refuse to write).
In Chapter 14, Nick continues to have good ideas (such as how to improve the food in the cafeteria), but now he is afraid to institute them for fear of them getting out of control. Nick's personality begins to change a bit. On the last day of school, Nick asks Mrs. Granger for the letter and she refuses to give it to him because "it's not over." Ten years pass with Nick still having adventures and people still using the word "frindle."
In Chapter 15, Nick is now in college and his trust fund from the frindle money matures. Nick receives a package from Mrs. Granger with a new dictionary featuring the word "frindle" and the signed and sealed envelope from years ago. The note simply says the following:
If you are reading this letter, it means that the word frindle has been added to the dictionary. Congratulations.
Mrs. Granger explains that she fought the word on purpose to prove her point all along. Nick sets up a scholarship fund in Mrs. Granger's name and gives her a gold writing implement as a gift. The engraving on the pen is as follows:
This object belongs to Mrs. Lorelei Granger, and she may call it any name she chooses.
—With love from Nicholas Allen