Write an article based on this "Start with 1 to 2 sentences telling your teacher what the letter is about. Give your teacher a few examples of what you appreciate about them. Finish the body of your letter by thanking them again."
This will tell your teacher what to expect from the letter. For example, you may be writing your teacher a letter of appreciation. Say, “I am writing this letter to tell you how happy I am to be in your class because you are the best teacher. This year has been hard, but you helped me do my best.” Consider why you are writing the letter, then choose the best examples to show your teacher what it is that you appreciate about them. To make your letter more personal, be specific and tell them how their actions made you feel.  You could write, “I appreciate the time you spent tutoring me after school. I felt like I would never understand multiplication, but you never let me give up. I’m so happy you’re my teacher!” If you’re having trouble deciding what to say, grab a sheet of scratch paper and do some brainstorming. Write down reasons why you like your teacher, times that they’ve helped you, or what you’ve learned from them. Then pick a few of your favorite reasons and use those in your letter. Write 1 to 3 sentences that sum up what you’ve said. Remind your teacher that you are appreciative of what they’ve done for you. You could say, “Thank you for being a great teacher this year. I’m so happy I got to be in your class. I hope you have an incredible summer!”