MELISSA BLOCK: Lots of college students heading back to school this week plan to go into the healthcare industry when they graduate. The pay is good. The field is growing. But anyone who wants one of these jobs has to make it through introduction to anatomy and physiology their freshman year, and it's tough. Zoe Chace from our Planet Money team has the story of one student taking it on.

ZOE CHACE: It's the first day of anatomy and physiology one at West Kentucky Community and Technical College. Instructor goes over the syllabus, the office hours, then moves right into the material which is pretty dense.

UNIDENTIFIED MAN: The humerus is the long bone found in the arm. Is this anatomy, or is this a physiological description?

CHACE: There's a guy in the front row taking notes. He's got safety goggles pushed up on his head - turns out he came straight from work.

Are you new to this stuff?

JONATHAN HARNED: Pretty much. Very new.

CHACE: How is it?

HARNED: It's a lot all at once.

CHACE: His name is Jonathan Harned. He puts up billboard advertisements for a living. He's 40 years old, got a military crew cut - he's wearing an American flag T-shirt.

Can you tell me what you are doing here?

HARNED: I want to be a nurse.

CHACE: Jonathan was the first one here. He was an hour and a half early. Now, Jonathan has spent 20 years building up to this moment. This is big.

And what did you think you were going to do when you grew up?

HARNED: I was going to get a job like my dad at some big factory or something and just stay there for 30 years and retire.

CHACE: Instead, he's had lots of jobs. And he punctuates each chapter with how much money he made at every stop. After he got back from the Marines, he tried a few things. Mechanic...

HARNED: Eight bucks an hour.

CHACE: Concrete finisher.

HARNED: 15 an hour - something like that.

CHACE: He drove a garbage truck.

Like a sanitation truck?

HARNED: Yes. The ones that pick up the big dumpsters.

CHACE: How was that?

HARNED: I got fat. I'm just sitting in a truck all day. I gained 25 pounds.

CHACE: He lost that job. Then he answered an ad in the paper for $12 an hour. He started putting up billboard ads 10 years ago.

HARNED: I make $17.61 an hour right now. In February I'll make over 18. And if I lose this job for any given reason, I'm back to 10 - $12 an hour. I have no security. I've had 22 years of reasons why I want to be here.

CHACE: Sitting in this anatomy class at community college, stakes are pretty high for everybody. People who finish a nursing program like this one have a much better chance of getting a job. And around here, healthcare jobs pay better. If you can get through this class and get this degree, it can be a magic key to a $19 an hour starting salary. Thing is, it's hard to get through even the first class. Jonathan's class is three hours long and lecturey. There's a ton of reading, and he hasn't been in school in 25 years.

HARNED: I didn't know how to study. I don't read.

CHACE: Hasn't taken a science class in that long.

HARNED: Chemistry - I can't do it.

CHACE: There's some chemistry in here you know?

HARNED: Then I'll mess it up.

CHACE: In fact, according to a national association, only 50 percent of people make it through this class. Unfortunately, it's required. I double checked with the dean, Karen Hlinka.

Is there anyway around this class if you want to be a nurse?

KAREN HLINKA: No.

CHACE: Do people try to get around it?

HLINKA: No. (Laughter). There's no way around. And there's a reason for that. You're not taking this class as just an elective. You're taking this class because it's building the foundation for the rest of your education. So you've got to get it.

CHACE: Lots of people don't. She's seen people taking the class again and again.

HLINKA: Four, five, six - on their seventh try. It was frustrating.

CHACE: Hlinka realized that a lot of her students just weren't ready. They knew how to memorize, but they didn't really know how to think. Jonathan's not insulted by that idea. He's like, yeah, that's my problem.

HARNED: Well, I thought it was a lot of memorization. And then we get in here in class, and he's talking about just implied answers. How do you know what the answer is if it's not in the book?

CHACE: The school set up a special class to slow down the material. And teachers, rather than just assigning the reading, are spending time teaching their students how to read the book. This seems to be helping. Instead of the national is 50 percent average, here about 70 percent of the students make it through the class - not everyone by a long shot, but still, one of the highest rates in the country.

Jonathan thinks he'll make an A or B in the class. He took a math pre-req over the summer, re-taught himself algebra, got a 96. If he makes it all the way through, he'll be the first in his family to earn a degree beyond high school. Zoe Chace, NPR News.