A new high school graduate may take out about $37,200 in student loans for college, according to a recent NerdWallet study. And for many of them, that won't be enough.

Thirty-eight percent of students borrow additional money for college via credit cards, home-equity loans and other nonstudent loans, according to a May 2020 report from the Federal Reserve.

The Student Borrower Protection Center, a Washington, D.C.-based nonprofit, has dubbed this the "shadow education finance market" because these options can lack transparency.

"A lot of these entities are operating with very little accountability or oversight," said Seth Frotman, the center's executive director.

Here's how to make sure you understand what you are borrowing — and whether the investment will be worth it.

Spot unfavorable loan terms. The line between student loans and loans marketed toward students can be murky. Frotman said the latter are often just personal loans.

You could pay much more if you can't tell the difference.

For example, if you borrowed a $2,000 personal loan at 20% interest, you would repay $3,179 over five years. A private student loan at 10% — roughly the highest current rate — would save you more than $600 over the same time frame.

The easiest way to avoid the shadow market is to borrow from the federal government. But if federal loans won't cover everything, closely read any alternative loan's paperwork. Beware features like high interest rates, double-digit fees and loans that don't require a credit check.

Check your school's credentials. Students should exhaust federal aid before turning to private options. But you may need to explore alternatives if you want to attend a nonaccredited school or program.

Accreditation is a process in which a third party reviews an institution or educational program — from its enrollment procedures to its curriculum and more — to ensure its quality. Only accredited programs can receive federal student aid.

If a school or program isn't accredited, be cautious about taking on debt to attend it.

You can see if an entity is accredited via the Database of Accredited Postsecondary Institutions and Programs. For nonaccredited options, look for other independent vetting — for example, if your state Department of Education has approved a career-based training program.

Determine the education's quality. In an April 2020 report, the Student Borrower Protection Center said alternative lending products are "frequently marketed toward borrowers at for-profit institutions."

If you are attending such a school, make sure you not only understand what type of debt you are taking on, but also if you will get your money's worth.

"There are good and bad schools in every sector of higher education," says Steve Gunderson, president and CEO of Career Education Colleges and Universities, a national membership organization for career schools. "What matters is outcomes."

You can find those in the Department of Education College Scorecard. Look at information such as median salary and median debt to help you better understand the potential value of a program.

If your program isn't in the College Scorecard, be mindful of data that comes directly from a school around things like job placement — especially if the numbers sound too good to be true.