When Leeia Isabelle started working on her college degree after serving three years in the Navy, she took a placement test and was put into a remedial math class at North Seattle Community College.

But did the former high-school honors student really need remediation?

Math is a major roadblock for community-college students. In the Seattle Community College District, about 70 percent of entering students need remedial math, according to a national standardized placement test.

Yet, taking remedial math for months — or even a year — can add to the time and expense of getting a degree, or make it more likely the student will give up and drop out, said Jill Wakefield, chancellor of Seattle Community College District.

And two national studies released in March showed placement tests "have terrible rates of predicting how students will do" in community college, said Georgia Stacey, spokeswoman for the New York-based Community College Research Center (CCRC), a national research program on community colleges.

With help from a $3 million, three-year Bill & Melinda Gates Foundation grant, the three Seattle Community College campuses are offering short math-refresher workshops to incoming students, part of a multipronged effort to help students skip math they don't need, compress the time students spend taking math they do need, and make college math more engaging.

These programs make it significantly more likely that students will finish their degree, Wakefield said. "Our enemy is time and money."

Isabelle, 24, took two math-prep workshops before she retook the college-placement test. On her second try, she skipped four levels and 1-½ years of remedial math, scoring well enough to place in pre-calculus.

"This was great for me," said Isabelle, who previously was an information-systems technician in the Navy and starts college this summer. "I just learned a few basics, and I remembered the basic principles. I was one point away from scoring into Calculus I."

Math skills get rusty if you don't use them, said Shannon Waits, coordinator of the community-college test-prep program.

"Who remembers how to do fractions?" she asked. "Or orders of operations? Or percentages?"

Wakefield said the initial results are promising; students who took the workshops have done well in the math courses they're placed in, finding them neither too hard nor too easy.

The CCRC recommends community colleges use several different measures to size up a student's skills in math and English before placing them.

Studies show a high-school grade-point average (GPA) is one of the strongest predictors of college success, Stacey said. Among local colleges, Green River Community College has been using high-school GPAs to help place students since 2004.

But because many Seattle Community College students graduated from high school years ago, the school can't rely on old GPAs to place students, Waits said.

Seattle Community Colleges are also using some of the Gates grant to compress and accelerate the amount of material covered in remedial math classes, and to offer different types of math classes that make the subject more relevant and interesting.

One of the most popular math offerings now is a statistics class that is closely tied to the way people use statistics at work, said April Jensen, special assistant to the chancellor.

Eva Walker, a 22-year-old Seattle Central Community College student, switched to the new class after struggling with algebra in high school and college. "I just thought that I couldn't do math," she said.

She's taking the class with her twin brother, Cedric, and both of them are getting A's.

"If you teach someone something that's going to be useful to them, they're going to be more engaged," Eva Walker said.

Katherine Long: 206-464-2219 or klong@seattletimes.com. On Twitter @katherinelong.