For Sam Eshaghoff, getting a high score on the SAT college admissions exam was more than a point of pride. It was a lucrative business. As Alison Stewart reports, other students paid Eshaghoff up to $2,500 each to take their tests using easily manufactured fake IDs. His scam came crashing down in fall 2011, when he was arrested for criminal impersonation and fraud. Eshaghoff has since accepted a plea deal, but the case still raises major questions about the integrity of the test itself.

The following script is from "The Perfect Score" which aired on Jan. 1, 2012. Alison Stewart is the correspondent. Katherine Davis, producer.

This past September, a 19-year-old college student named Sam Eshaghoff made national news when he was arrested and charged with fraud and criminal impersonation. His crime was taking the SAT and ACT tests for other people. He was so good at it other students paid him thousands of dollars to take the exams for them.

The district attorney who charged him says Sam Eshaghoff was able to take the SATs at least 16 times which has raised questions about the integrity and security surrounding one of the most important tests millions of high school students ever take.

Tonight, for the first time, Sam Eshaghoff tells us how and why he did it.

Sam Eshaghoff: I thought that there was an easy way to make money. And just like any other easy way to make money, it's always too good to be true.

Alison Stewart: Who told you you were in trouble?

Eshaghoff: My parents got a phone call saying that there was a warrant for my arrest, which was scary and shameful. I felt like my world was going to come crashing down.

Until he was arrested in September, Sam Eshaghoff seemed like the perfect kid. At New York's Great Neck North High School, he was a top student, vice president of the business club and a varsity athlete, but what may have been his greatest talent was the one that got him in trouble: his ability to ace standardized tests, which was how he began a double life as a con man.

Kathleen Rice: I would call him an academic gun for hire. That's what he was.

Stewart: People just needed him to get a job done and he got it done.

Rice: And he was the man.

Nassau County District Attorney Kathleen Rice filed criminal charges against Eshaghoff and the students who hired him.

Rice: This was a huge fraud from my perspective. This was lots of money changing hands, there were high stakes involved, and there was forgery, there was criminal impersonation. That's a fraud. That's a fraud on many different levels, but most importantly against the kids who play by the rules.

Stewart: During the course of your investigation, what did you discover about the process of taking the SAT and the security associated with taking an SAT test?

Rice: How incredibly easy it is to cheat the system. There is absolutely no security in place whatsoever to prevent criminal impersonation like we see here from happening.

Stewart: So if I went up to any of those kids and I say, "Do you know what this guy did?", they'd all know?

Eshaghoff: Every single person would know who I am and what I do.

Eshaghoff says paid test takers were an open secret among students at Great Neck North. He became the best known, but he says he was not the first.

Eshaghoff: I had heard of it happening successfully in my own high school.

Stewart: So tell me about taking the mental leap from "well, I heard other kids doing it" to "I think I'm going to do this."

Eshaghoff: Well, it all started with some kid approaching me. He's like, "Yo, you're good on your SATs and I'm not. And you know this is possible so how much is it gonna take?"