Four years ago, when they were just 19, twins Alex and Brett Harris released their best-selling book, "Do Hard Things." The book encouraged teens to rebel against the low expectations of today's culture by stepping out of their comfort zones and taking on challenges no one expected them to address-fighting against abortion, learning an activity like public speaking, refusing to watch bad movies, or simply performing unassigned household chores-all for the glory of God.

Now seniors at Patrick Henry College (PHC), in Purcellville, Va., the Harris twins are ready to carry that message into adulthood. As he reflects on his time in school, Alex Harris has one main piece of advice for next year's freshman-beware the freedom college offers and embrace the new responsibilities as challenges and opportunities to shine.

When "Do Hard Things" came out in April 2008, the twins became mini-celebrities in the nationwide Christian homeschool community. But before that, they were just normal teenagers-with a passion for great things. They first got the idea behind the book in 2005, when their dad set a huge stack of books on the kitchen counter and announced that he was putting them on an intense reading program for the summer. With topics ranging from history, philosophy, theology, science, business and journalism, the pile looked a bit intimidating. But as they read, they become more and more concerned about their generation and the misconceptions about the challenges teens were capable of taking on. In an effort to share their thoughts, the brothers started a blog, founded The Rebelution, a movement to encourage teens to disprove the world's low expectations for them, and later wrote "Do Hard Things."

The book's publication brought opportunities for speaking engagements, traveling and more writing. And after all the attention the Harris brothers got while still teenagers, one of the best parts about college was being able to be a normal student, Harris said. The twins came to PHC with a desire to build relationships and earn respect based on their actual interaction with other students, and not on things others had heard or read about them. "Thankfully, we were able to come in with a terrific group of classmates who embraced us as 'Alex and Brett, normal guys' and not 'Alex and Brett, authors and speakers.' … so that was really good and healthy and what we wanted," Harris said.

Frank Guliuzza, a Government professor at PHC and pre-law advisor for Harris, said that the brothers conducted themselves in a way that would never lead anyone to believe they once rode on private jets, spoke on tours with Chuck Norris, or were involved in presidential politics. "I think everyone was pretty amazed by how genuine they were in their willingness to blend in with other students," Guliuzza said.

Although Harris was an impressive student-seemingly successful at anything he put his mind to-he impressed Guliuzza most by the way he handled defeat. Guliuzza recalled one basketball game in which Harris and his team started ahead, but ended up losing by a huge margin. Harris didn't let it discourage him but continued to play with enthusiasm and energy, Guliuzza said: "I got to see this guy when he was supremely successful [and] I also got to see him when he and his team were anything but, and he seemed to carry himself the same way."

Coming to PHC let them slow down and really get to know people, something in which they did not have enough experience. "People are fascinating creatures," Brett said. "and anyone who thinks they have them all figured out, labeled, and filed away is very wrong. I came to this school having interacted with lots of people, and just had so much to learn about being a friend, understanding and working with people, understanding how I came across to people."

Alex echoed the exact same sentiment. "I wish there had been a way to make marriage and family and off-campus life work better with relationships on campus," he said, "and have more opportunity to connect, particularly with classes that came in after my class. Everyone here is worth getting to know."

Graduating in May with a degree in government, Harris plans to attend law school in the fall. He got accepted at the nation's top three-Harvard, Yale, and Stanford-and has chosen to enroll at Harvard. (Brett plans to be married in June, move to the Seattle area, and continue writing.) "[L]aw intersects with numerous fields, including government," Harris said. "Legislation, regulation, and judicial decisions are all about making and interpreting the law-so there's a very strong connection." While his plans are far from settled, Harris said he believes God is calling him to use his law degree to make a difference in the arenas of public policy and government. "That could include arguing cases in court as an appellate lawyer, ruling on cases as a judge, influencing the public policy conversation at a think tank, or running for political office-or more than one of those!" He still urges his generation, now young adults, to realize the importance of becoming involved politically by being engaged and informed.

Although the dismal job market and the rising cost of higher education has caused some to question the value of a college degree, Harris believes that the investment was worth it, even for someone who already had accomplished more than the average teenager by the time he started submitting his college applications: "[It was an] opportunity to grow, not just in knowledge, but in maturity and responsibility." College also gave Harris the opportunity to pursue his passion for politics. Unlike many students, who change their major multiple times, Harris planned to major in government from the beginning and stuck with it all the way through.

Harris encourages students considering college to embrace their responsibility, as well as their freedom. Next year's freshmen will discover they have a lot more freedom than they've ever had before, as well as a lot more responsibility, Harris said. Those who focus on the freedom will self-destruct, while those who focus on the responsibility will not only excel, but thrive, he said.

Even though Harris values the time he spent in college, he cautions others to think through their reasons for going before sending in their applications. Many teens feel pressured to go to college because it's the next step, Harris said. Even though a college degree can be important, going to college aimlessly just wastes time and money, he said: "If you decide to go to college, have a sense of direction, because that will really ground you and make your time more productive."

With reporting by John Rust.