Idiom: "to make big bucks"
Example 1:
Joe: Whatever happened to Tony, that guy who we went to high school with?
Sam: You didn't hear? He developed some app for smart phones and he's making big bucks now!
Joe: Yeah, I can see that. He was really smart and creative. Good for him!
Example 2:
Sally: I heard that Stacy wants to become a elementary school teacher.
Grace: Your kidding? Teachers don't make a lot of money!
Sally: Well, she knows that no one becomes a teacher to make big bucks. She just has a really special heart for children and she wants to make a difference in their lives.
Grace: Oh really? Well, then I hope everything works out for her.
Meaning: "to make big bucks" is an idiom that means to make a lot of money or to earn a really large salary compared to others.