With student loan debt topping a collective $1 trillion, most families are being affected by the college debt crisis these days. As the college-bound look for ways to cut their costs, it is useful to note that some states are responsible for a higher degree of college indebtedness than others.

Here are the top three stateswhere at least 75% of 2011 graduates held student loan debt -- with average debt loads of more than $24,000, to boot.

1. North Dakota
A whopping 83% of graduating students have piled on college loan debt, the highest by far of any in the study by The Project on Student Debt. With an average debt load of $27,425 per student, the amount of debt produced by higher education in North Dakota is truly stunning.

2. South Dakota
Neighboring South Dakota is second in the lineup, with 76% of studentsleaving the state's colleges with an average loan total of $24,323. South Dakota has actually improved its standing from the 2008 Student Debtstudy, however, the year in which it ranked No. 1 with 79% of the graduating class encumbered by student debt.

3. New Hampshire
While this New England state ranks No. 3 here -- 75% of graduates leave the state's schools with debt -- it holds the No. 1 spot for the average debt load, an astonishing $32,440. This dubious honor spurred the Granite State Management & Resources department to commission a study from the New Hampshire Higher Education Assistance Foundation on why the state has the highest level of student debt in the country.

Why is student debt so high?
Basically, this is the question New Hampshire is asking, and the answer is anything but cut and dried. Indeed, the study's author, Brian Gottlob, noted at a press conference recently that not only has the problem been developing and growing over the past 10 years, but it is so multifaceted that there is no single approach that could effectively cure the state's college debt dilemma.

While New Hampshire's study notes several reasons for escalating college costs -- household wealth, college choice, decreased state aid, and rising tuition -- it's that last one that seems to be at the heart of the matter. The Federal Reserve Bank of St. Louis noted earlier this year that tuition costs have risen 165% from 1993 to 2011, while health care costs, as a point of comparison, rose only 100%. This makes rising college costs a major contributor to exploding student debt levels.

Knowledge is the best defense
Despite the seemingly grim outlook, experts note that preparation is the best way to avoid unnecessary costs. The Project on Student Debt suggests being cognizant of costs outside of tuition and fees, such as local cost of living, books, and transportation when calculating a particular college's true yearly cost. Also, the group strongly advises using the net price calculators available on a given college or university's website to get a more personalized estimate.

College likely isn't going to get any cheaper, but shopping around and avoiding costly surprises may help keep you or your college-aged child from becoming another victim of onerous student loan debt.

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