Ingenious teenagers can find every manner of reason to take a pass on summer school: There's the two-week family vacation in the middle of the four-week session, not to mention the potential for a day job scooping ice cream-or the fear that they might bomb at cramming a semester's worth of work into a month. In the digital age, however, none is reason enough. The rapid spread of online learning at the secondary level-experts estimate that more than half of all school districts offer some virtual coursework, up from just 30 percent two years ago-is now creating "anywhere, anytime" flexibility for summer students, too.

　　While the total numbers are still small, many hundreds of students around the country will be signing on in the next week or two for everything from U.S. history to human space exploration. In California, Graham Petersen, who just finished his junior year in Palo Alto, will study Algebra II through the online arm of Oregon's Salem Keizer school district while working as a teacher's assistant in a children's program. "This is no shortcut-it's the full course. But you can work at 11 o'clock at night," says Robert Currie, executive director of Michigan Virtual High School, whose courses, like most, are available nationally.

　　Beyond convenience, there are instructional reasons to consider the virtual classroom. Those who have struggled in a course during the year often find that the online format makes it easier to master the content. "Most students finish with A's and B's, because teachers don't let them go through with D's," says Jan Bleek, principal of the Internet Academy, an arm of the Federal Way district near Seattle that is offering 45 summer courses at $180 each. "There's lots of revision, a lot of work that goes on in depth between teacher and student after work has been submitted." While grading policies vary, kids often are free to retake assessments or to work through several practice exams until they're ready to be tested. "I got a B-the highest grade in math I've ever, ever gotten since sixth grade," says Petersen, who took the first half of Salem Keizer's online Algebra II class this spring after failing the course first semester.

　　Success depends largely on actually tackling the content, of course-and nobody (other than parents, perhaps) will be breathing down a student's neck. So it's important to be realistic about whether online study is a good fit with a teenager's learning style. "The No. 1 thing is, are you capable of working on your own?" says Kathy Armstrong, an English teacher at Harris County High in Hamilton, Ga., who is also an instructor for Virtual High School. Since material is presented as text rather than by lecture, being a proficient reader is a must.

　　31. According to the first paragraph, the reason why teenagers used to have an excuse for not taking academic summer courses is that

　　[A] they had more important things to do.

　　[B] they had other distractions and obligations.

　　[C] society wasn't as competitive.

　　[D] they were better at making excuses.

　　32. Why is Graham Peterson studying online?

　　[A] Because he is not up to the required standard in algebra.

　　[B] Because he likes working at night.

　　[C] Because he likes studying at night.

　　[D] Because he wants to study and work.

　　33. It can be inferred from the text that students usually get A's and B's because

　　[A] studying online is better and more convenient for them.

　　[B] the teachers are not as strict and give higher scores than at regular schools.

　　[C] most of the students studying online are smarter than average.

　　[D] the teaching and assessment process continues even after students have submitted their initial work.

　　34. According to the text, how is studying online different to conventional study methods?

　　[A] It's suitable for anyone.

　　[B] It requires some different study skills.

　　[C] Grading policies vary.

　　[D] Students can take more practice tests before taking the real exam.

　　35. The best title of the text might be

　　[A] Learning via the internet is easy.

　　[B] Learning via the internet is relaxing.

　　[C] Learning via the internet can be convenient and instructive.

　　[D] Summer school is easier than before.