You might wonder why a teenager would want to spend her last summer before college taking precalculus.

But Emily Johannsen, of Austin, Minn., has no regrets.

The class, which she took for free online, helped ease her transition to the University of Minnesota Duluth, where she's now majoring in biochemistry.

"It did give me an extra jump start," said Johannsen, 18, who will be a sophomore this fall. In fact, she said, she ended up getting all As in her first college math course, thanks in part to a summer program called Math Prep.

A year ago, Johannsen took part in the first full session of the UMD program, which was designed to encourage students like her — from low-income, minority or first-generation families — to pursue careers in fields like science and math.

This week, Johannsen, who is of Filipino descent, is back as a student mentor, sharing her experiences with a new batch of high school grads at a weeklong Math Prep summer camp on the Duluth campus.

Rachel Breckenridge, a math instructor who started the program, said she was looking for a way to help "freshmen from underrepresented groups" flourish in the STEM fields — science, technology, engineering and math.

Often, she said, students start out with a passion for those subjects, "but they don't have the success rate." Her goal, she said, was to give them both a boost academically (through the online courses) and a chance to connect with one another, and form support networks, before school starts. The program is funded with $38,000 in state and university grants.

This week, 20 Math Prep students, all incoming freshmen in the college of science and engineering, will get a taste of life on campus, with mini-sessions in biology, chemistry, microbiology, engineering and a cruise on a research boat on Lake Superior. They'll also get a crash course in "financial literacy," dorm food and exploring Duluth.

To Johannsen, the experience was invaluable. "It helped me get into shape, basically, on how to be a good student."

maura.lerner@startribune.com