PORTLAND – A growing number of Maine high school students are taking courses where their classmates – and their teachers – are in other states and countries.

Hundreds of students across the state are taking courses over the Internet that range from Mandarin Chinese to astronomy to Advanced Placement calculus. The emergence of online teaching gives students more learning options for basic and advanced courses.

Virtual High School, a Massachusetts-based nonprofit company, may be the largest provider of virtual classes in Maine. Students in Biddeford, Calais, Cumberland, Falmouth, Hiram, Madison, Poland, Scarborough and Thorndike take Virtual High School courses, and high schools in Yarmouth and Lee are expected to offer classes next fall.

Maine is an ideal place for online courses because the state’s many small rural schools are unable to offer a wide range of classes, said Liz Pape, president of Virtual High School.

“It gives them access to courses and access to students they might not otherwise get to meet,” she said.

Class size for the online courses is limited to 25 students. The courses meet learning standards in Maine and elsewhere.

Taking classes online isn’t the same as a real classroom, some students say. But without them, students like Calais High School senior Emily Wilkinson wouldn’t take some of the advanced courses they need.

Wilkinson took an online Advanced Placement biology course where all classwork and discussion took place online. She even dissected a fetal pig and a frog over the Internet.

After taking the course, Wilkinson earned the highest possible score on the Advanced Placement biology exam and will attend Harvard University this fall with some college biology credits already under her belt, she said.

Virtual High School is serving 258 Maine students this year. But other companies also offer online courses in Maine, said Wanda Monthey,

Advanced Placement director for the Maine Department of Education. Most states also create their own online course offerings, and Maine is working to develop such courses here, she said.

At Greely High School in Cumberland, five students are taking virtual courses this semester including astronomy, psychology and an English course based on the Jules Verne novel “Around the World in Eighty Days.”

Greely junior Nate Wildes said he added the English course to his schedule of regular classes because he needed some humanities credits and liked that it also involves social studies.

He’s paying online visits to the countries featured in the novel and learning about their history and culture.

“It was an opportunity to take a class that wasn’t offered here,” Wildes said.