Good grades can open many doors in college: scholarships, acceptance into certain majors and better chances of getting into graduate school.

Likewise, bad grades can close those same doors, possibly requiring students to repeat classes to reopen them. But what defines a good or bad grade largely depends on the goals students set for their collegiate career, academic experts say.

"We really want our students to work with us to define what they think good grades are for them to be successful. At a bare minimum, it's going to be a 2.0 (grade point average)," says Chris Jensen, assistant vice president for student success at Western Kentucky University. "That's what they need to graduate, but we want our students to strive for more than that."

Broken down by letter grade, a student with all A's can expect to earn a 4.0, all B's to equal a 3.0 and all C's to hit the 2.0 mark. GPA is calculated over a student's collegiate career by adding the resulting grades of classes together to gauge academic performance.

While a 2.0 may be enough to graduate from many college programs, it may fall short depending on major requirements. Certain programs – particularly those with an emphasis on science, technology, math and engineering – may require a 3.0 or better. Similarly, admission to graduate school typically requires a GPA higher than a 2.0, especially for competitive programs.

Falling below a 2.0 can come with consequences as dire as academic probation, suspension or even expulsion. Poor grades may also disqualify students from scholarships or financial aid and cost students more time and money when pursuing a degree.

GPA also matters for potential transfer students. Community college students looking to transfer to four-year institutions will be best served by earning good grades first.

"Students should strive for more because (admission) is competitive," says Tricia Rizza, an associate professor of English at Florida's Tallahassee Community College, who helps develop academic programming for first-year students at the school.

While good grades can be relative to a student's idea of success, here is what experts have to say about earning high marks.

Go to Class

Rizza tells her students to "be purposeful, be responsible and be intentional" with their education. A big part of that is going to class, even when there are other competing interests. And if a student must miss class, he or she should notify the professor.

In college, students have more flexibility to skip class because attendance policies vary by professor, but that isn't an excuse to miss class. Experts say students should attend class, take notes and engage with the material, the faculty and their classmates.

"Once they start in the classroom, students need to take an active role in it," Jensen says.

That means meeting classmates, being engaged and sticking around for the whole class, not just part of it.

Read the Syllabus

Students should "read the whole syllabus" emphasizes Heather Page, executive director of academic advising at Eastern Washington University. It's there students will find details on deadlines, assigned readings, extra credit opportunities and more. Knowing what's in the syllabus can give students an idea of what to expect over the course of a semester. The typical syllabus often includes a class description, a calendar, the grading rubric, attendance policies and required materials.

Work Ahead

With the syllabus serving as the class road map, attentive students know what assignment is around the bend.

"Today content is offered in these hybrid models where your information is online ahead of time. And it's also delivered in the classroom. So what can you be doing to work ahead?" says Stephanie Bannister, assistant vice provost for student success at Kansas State University. Students should use the information, she says, to get a jump start on class reading assignments.

Do the Homework

"Even if you don't get a grade for it, what the faculty have identified as important to being successful in the class is built into the homework," Page says, adding that's why it's important for students to complete every assignment, regardless of credit.

And if students get stuck on their homework – like any other assignment – they should ask for help.

"There are people out there to help them be successful with homework and on exams and throughout their entire collegiate experience," Jensen says.

Go to Tutoring

"Across the board, I would say all universities and colleges offer some sort of tutoring," Page says. Some colleges may offer group tutoring, while others opt for one-on-one sessions. Likewise, some academic departments may offer tutoring at some colleges, while at others it may be grouped under a specific learning center.

"Good students are good students because they go tutoring from the very beginning, or they go to the study groups from the very beginning," Page says.

Experts emphasize asking for help before falling behind. "A student should ask for help as soon as they have any issue, don't let it grow," Jensen says. In addition to seeking out tutoring, students should ask instructors for clarity on class materials if needed.

Meet With Faculty and Advisers

Faculty office hours exist for a reason, and experts encourage students to take advantage of that time.

"One of the most underutilized (resources), I think, is our faculty members and their office hours. They have those for a reason: to help our students be successful, to help them through the material and prepare for exams and other things," Jensen says.

Similarly, students should seek out academic advisers to connect with campus resources and set class schedules. Advisers, Jensen says, can help students stay on track for graduation by helping them set reasonable course loads and expectations.

Page recommends that students take 15 credits per term in order to complete a degree within four years. She encourages students to ask questions about degree requirements, understand the courses and credit hours needed and check on progress annually.

Find a Balance

The reality, for many students, is that a job is necessary to pay for college. According to a 2015 report from the Georgetown University Center on Education and the Workforce, "more than 70% of college students have been working while enrolled" in the last 25 years. The Learning While Earning study found that nearly 40% of undergraduate students worked up to 30 hours per week.

While that may be necessary for some students – particularly adult learners – experts caution against working too much.

“One of the things we tell our students is not to work more than 20 hours a week during that first semester," Jensen says.

Bannister recommends that students to start out with a campus job of 10-15 hours a week and add more hours if they feel capable.

Challenge Yourself

Rizza encourages students to think about how they learn, whether that's the time or space where they prefer to do homework and their own learning style. And once they're aware of how they prefer to learn, she encourages them to see what they're capable of.

"College, as with any pursuit of learning, is not always easy. And I would argue that it shouldn't be because if it is (easy), you're too far into your comfort zone, you're not really, pushing outside that or growing," Rizza says.

Though it may be tempting for a student to coast in his or her first year out of high school, academic experts caution against it. “If you come into college wanting to take an easy semester or an easy quarter and ease into it, you're probably already behind," Page says.

And never get discouraged by setbacks along the way.

"Every single person's journey looks different, and it's fraught with challenge and opportunity," Bannister says.