Sarah Siddiqui, 18, right, answers a question as Zkiyya Mowlana, 18, listens after Siddiqui gave a speech about the Israeli-Palestine conflict April 17 during a Speech 108 class, a college course offered at Gaithersburg High School. (Astrid Riecken/FOR THE WASHINGTON POST)

As college finals approached, Leah Pope studied more than ever for philosophy. Hallie Lappin pored over her notes for criminal justice, and Andrew Lloyd reviewed the semester’s work in speech class.

All are high school students.

They have had early experiences of college life, taking full-on college courses as high school seniors in Montgomery County to get a glimpse of what lies ahead: fewer scheduled hours of class, more independent work and less hand-holding from instructors.

They reflect a growing interest in many areas of the country to go beyond work that is college-level and try college itself.

At their school, Gaithersburg High, that’s easier to do than at most places, with eight courses taught this spring by professors in the same classrooms where students take high school English and algebra. More than a third of the class of 2012 has taken at least one college course. “It’s a boost of confidence when they say, ‘Oh, I can do this,’ ” said Principal Christine Handy-Collins.

Early college opportunities are often overshadowed by the immense popularity of Advanced Placement and International Baccalaureate courses, which teach college-level material and can lead to college credit when students test well on exams. But college courses in high school are on the rise in many states, said Adam Lowe of the National Alliance of Concurrent Enrollment Partnerships.

Experts say one goal is to blur the lines between high school and higher education, with research showing that senior year, in particular, can be a dead zone of sorts for students who are done with most requirements but not yet onto the next challenge. Taking college courses ahead of time can keep them engaged.

“It means that kids can move at their own speed, and there’s no reason they should have to go in lock step if they can go faster,” said Chester E. Finn Jr., president of the Thomas B. Fordham Foundation, an education think tank.

In an unusual approach, many of Montgomery’s public high schools offer college courses, taught on site by faculty from Montgomery College and, to a lesser extent, the University of Maryland. Credits count only on college transcripts, not toward high school graduation.

Students who are the first in their family to go to college, and perhaps uncertain about their prospects in higher education, also get a chance to try it out in the supportive environs of high school, proponents say.

The economics can be appealing, too. Through a special grant program, half of Gaithersburg High’s college students pay no tuition. For those who do pay — about $440 for a three-credit course — community colleges’ rates are lower than typical costs at four-year institutions.

Through AP testing and the college program at Gaithersburg, Austin Duff accumulated 25 credit hours before heading to the University of Maryland Baltimore County a year ago.

“He walked in five hours short of sophomore status,” said his mother, Deanna Duff. Now he will complete his bachelor’s and master’s degrees in computer science in four years, she said, which means a lower overall bill and fewer college loans.

In the Virginia suburbs, where dual enrollment has historically focused on career and technical courses, academic courses now are a big push. Such offerings have grown 80 percent over three years, said Ruthe Brown, director of dual enrollment at Northern Virginia Community College.

“It’s all part of the same philosophy: How do we get our kids to college at less expense?” she said.

In Alexandria, T.C. Williams High School projects that the number of students taking college courses will almost triple next year, to nearly 300 students.

Schools officials say they have a strong AP program, but students don’t always score high enough on AP exams to earn college credit. In actual college courses, students earn credit for passing the class. “It’s to give students an alternative,” said Michele Coffman, coordinator of the college program. xxxxxxx

In room D-42 of Gaithersburg High recently, Saba Rahman took her turn at a lectern, presenting her findings about cosmetics testing on animals, using all she has learned about speech-making and persuasion.

The 9:07 a.m. bell interrupted.

The hallways filled with students, but Rahman’s classmates did not rise to leave because Speech 108 is a college communication course, and in this world where high school and college converge, there is the occasional clash of form and structure.

College classes sprawl over more than one high-school class period. The classes meet twice a week. On some days, students meet in a special “college” lounge to socialize and study. They carry or wear orange badges that identify them as part of what Gaithersburg calls its “College Institute.”

“You must have done a lot of rehearsal,” professor Ruthie Hempel told Rahman, 17, after the presentation. She cited Rahman’s clarity, her eye contact and her well-researched PowerPoint.

“I thought you had a good balance of logic and emotion,” Hempel said, as other students chimed in with critiques.

Camila Chile, 17, said the college experience has meant a new approach — fewer quizzes and warm-ups, and bigger tests. “You have more freedom in the college classes,” she said. “But you have to put in more effort.”

Hallie Lappin, 17, said the pace is a change, too: a class on Monday and Wednesday, for example, followed by four days off. “There’s a lot more studying that you really have to take the responsibility on for yourself,” said Andrew Lloyd, 18.

Program coordinator Susan Byrne keeps an eye out for students who might not be making the leap — “a kind of safety net,” she said. “The high fliers don’t need it but there are also some students who just woke up junior year, and they may need support.”

For college faculty, the idea also can take some adjustment.

Muhammad Kehnemouyi, chairman of the physics and engineering department at Montgomery College, recalled momentarily wondering how serious high-schoolers would be. He was surprised.

“They did all of the assignments on time,” he said. “They participated in the discussion. And the stuff they designed was really good.”

Ryan Stringer, who teaches philosophy, said that his Gaithersburg students performed better overall than his older students at Montgomery College. “Certainly, their attendance is better,” he added.

The collaboration with Montgomery College goes back a decade and has led to more than 6,000 county students earning college credits. Enrollment has been highest for the past four years. Schools tend to favor courses that do not overlap with AP — engineering, for example, or anthropology.

“It’s not about rushing through,” said Genevieve Floyd, supervisor of career and post-secondary partnerships for Montgomery’s schools. “It’s about getting that experience earlier and smoothing the college transition.”

Partnerships between high schools and colleges across the country take many different forms.

Last year, a new program called Academy of Health Sciences brought 100 ninth-graders to Prince George’s Community College, with the idea that by graduation, many would earn both a high school diploma and an associate’s degree.

In the District’s public schools, efforts to expand dual-enrollment programs are underway, officials said. Existing programs include a collaboration between George Washington University and a group of students at School Without Walls.

In Montgomery, each high school is encouraged to develop a college-going culture.

Wheaton High School Principal Kevin Lowndes started with one class and 12 students six years ago, and now counts 57 students in five courses. Most will be among the first generation in their families to attend college and get free tuition through Montgomery College’s grant program. “We’ve seen great outcomes,” Lowndes said.

Northwood High School students travel off campus for college courses. “They just kind of blend in,” says Principal Henry R. Johnson.

Walter Johnson High School partners with U-Md. faculty. Chris Garran, a former principal, said the initiative has not reduced AP enrollment — which is as strong as ever and growing.

This year, there were 177 college enrollments for such courses as engineering, social psychology and the history of terrorism — all of which come with a college price tag — more than $1,000 for a three-credit class, similar to tuition at College Park.

“We consider it successful,” said Eric Johnson, assistant director of extended studies at U-Md. “It has done nothing but grow.” Grades have been mostly A’s and B’s, he said, with only a few students who faltered because of “senioritis.”

One perk: On most days when the college class does not meet, seniors who take such courses are not required to show up at school until third period, which means some sleep in — another kind of preview of college life.

“The idea was to not just have the class,” Garran said, “but to have something close to a college experience.”