MINNEAPOLIS (AP) — Efforts to engage Minnesota teenagers in pregnancy prevention may be paying off.

At Minneapolis South High School, Jasmine Powell led a group of students wearing matching black sweat shirts who struck up a conversation about teen pregnancy with a group of eight boys amid the hubbub of the lunchroom. They’re from a project called Sexually Responsible And Mature Teens, or SMART. The 11th grader confidently asked if the teens had thought about how to prevent a pregnancy.

“It’d be important to use birth control, right? And to know how to use your birth control?” she said, generating some nervous giggles, as well as a few blank stares.

SMART is one of several projects across the state engaging teens to bring pregnancy rates down. Experts say those efforts are working, as the birth rate among Minnesota teenagers has plunged nearly 40 percent in the past two decades.

Mary Jo Chippendale, who follows birth rates for the state health department, told Minnesota Public Radio (http://bit.ly/KfBeAf ) some of the more obvious potential explanations don’t fully explain what’s happening.

While sex education classes in Minnesota tout abstinence as the only 100 percent effective way to avoid pregnancy, Chippendale said there hasn’t been a big change in sexual activity over the last 10 years. Survey data show the percentage of teens who had had sex dropped about 10 percentage points from the early 1990s to 2001, but held steady or increased slightly over the last 10 years while the birth rate continued to drop. In 2010, about 20 percent of ninth-graders and half of 12th-graders said they’d had intercourse.

And the abortion rate among Minnesota teens ages 15 to 19 has declined at a similar pace as the birth rate. So Chippendale said something else clearly must be happening.

“It’s probably more likely that they’ve increased contraception use,” she said.

Brian Russ, executive director of the Annex Teen Clinic in Robbinsdale, said better information about contraception, and smarter use of it, are probably factors. But he said engaging teens in conversations about pregnancy that include their attitudes and feelings about the future also can have a big impact.

“Absolutely young people need access to preventive health care services, contraceptives and education, but they also need a reason to delay pregnancy. They need a sense that, ‘You know what? I’m not ready,’” Russ said.

Judith Kahn, executive director of Teenwise Minnesota, said understanding the consequences of pregnancy can have a real influence on teens’ actions — and ultimately the birth rate.

“If young people have a sense of confidence and competence about themselves, if they recognize that they do matter in the world and that they have the ability to make a difference going forward, they’re less likely to engage in behaviors that will defer those dreams,” she said.

Elsewhere in Minnesota, Project 4 Teens recruits youth leaders from Mankato high schools to talk to younger students about healthy choices, including preventing pregnancy.

In Hennepin County, 42 clubs at middle schools in areas with higher pregnancy rates are helping teens develop communication skills and talk about healthy relationships through a program called It’s Your Future. There’s also a component for sexually active high school students. The program received a federal grant of $16 million in 2010 to use over five years, and organizers hope to add more schools next year.

Katherine Meerse, who directs the program, said contraception and pregnancy isn’t part of the program, which includes weekly meetings and a community service project. But Meerse said research shows it’s still very effective, leading to a 53 percent lower risk of pregnancy. She said the program has other benefits, too.

“They’re also less likely to drop out of school, to get suspended from school, or to fail courses,” she said. “We got funded to do it because it’s been shown to reduce teen pregnancy, but it also has these great academic outcomes.”