Hackers attempted to change grades at a Fairfax County high school, using a cunning attack that began with an email from a school panel charged with upholding honor and integrity, according to a search warrant. Oakton High School in Vienna, Va., is just the latest in a string of secondary schools, colleges and universities nationwide to be targeted — often by meddling students — in attempts to turn F’s into A’s in virtual grade books.

A Wall Street Journal analysis of data from more than a dozen large US public universities found that in the 2014-15 school year, the schools recorded 5.1 reports of alleged cheating for every 100 international students. They recorded one such report per 100 domestic students. Faculty and domestic students interviewed said it appears that substantial numbers of international students either don’t comprehend or don’t accept US standards of academic integrity.

The University of Iowa suspects at least 30 Chinese students of having used ringers to take their exams. The case offers a look inside a thriving underground economy of cheating services aimed at the hundreds of thousands of Chinese kids applying to and attending foreign colleges. Coaching services author essays for clients. Handle their homework. Even take their exams. All for about a $1,000 a course.

As tens of thousands of Chinese students prepare to study in the U.S., they might reflect on the experience of some of those who went before them. According to an estimate by a U.S. education company, some 8,000 Chinese students were expelled from American universities last year alone – and the main reasons were poor grades and cheating.

An unusually high number of students at Stanford University are suspected of cheating during the most recent term, putting faculty members and administrators of the prestigious institution on alert. University spokeswoman says that in the 2013-2014 academic year, 83 students violated the honor code. In the most recent term, the newspaper reported that one instructor believes that 20 percent of students in a large introductory course may have cheated.

An eight-month investigation by former federal prosecutor Kenneth L. Wainstein has found that more than 3100 University of North Carolina at Chapel Hill students – almost half of them athletes — were given credit for "irregular" (read: nonexistent) classes over an 18-year period from 1993-2011 as part of a organized scheme that allowed many to remain sports-eligible.

Thirty-five former school officials have been implicated in a test cheating scandal, and have been given a deadline to surrender to authorities in the state of Georgia. The accused in the city of Atlanta face counts of racketeering, making false statements and conspiring to improve test scores to win cash bonuses.

A cheating scandal at Harvard College has grown, and this time, the administrators, not students, are under fire. The school has apologized for the way it handled a secret search of the email accounts of resident deans. It conducted the search in an attempt to find who leaked information about the scandal to the media last year.

Easy A's may be even easier to score these days, with the growing popularity of online courses. Technologically advanced students are finding ways to cheat that let them ace online courses with minimal effort, in ways that are difficult to detect.