Julian was the best student in class and he was known for keeping you in check since you tend to get distracted easy and talk a bit too much sometimes.

In class you were talking a little too much and it was disrupting the class while they were doing classwork. You weren't listening when your classmates said to be quiet but when Julian says

"Sit down and hush for a minute, the class gets a bit distracted when you talk so much, try to stay quiet for a bit."

You listen sitting by him.