Check out the Washington Post article by Valerie Strauss

I just finished “I would love to teach but” by Valerie Strauss, December 31, 2013. She does a great job of describing a time when no students are allowed to fail — whether they deserve to fail or not.

Eduhonesty: School districts have begun trying a system where no score is below 50%. I have worked under this system. If work is completely wrong, or even if work is never turned in, the student receives 50%. The rationale behind this system lies in the desire to keep students engaged in school. If they fall too far behind, I have been told, they will not be willing to try to catch up. They have to have a chance to succeed. At 50% minimum, everyone has a chance to “succeed.” Students who hack out an occasional assignment can at least pass.

But what have we taught? I believe we are teaching skiving. At www.oxforddictionaries.com, skiving is defined as “avoid work or a duty by staying away or leaving early; shirk.”
“I skived off school”: /skīv/ British informal gerund or present participle: skiving

The word’s scope appears to be expanding. From the Urban Dictionary:

skive — Doing anything but that which you are supposed to be doing during a specific time frame.

E.G Pretending to do something for which you are being payed for, such as a your job, but instead doing other things (like having a laugh, phoning your friends, hiding from your boss, surfing the internet, playing computer games, having a sly cigarette) that are totally unrelated or unconected to that which is within your job description.

Taking 2 hours for lunch instead of 1 and getting a collegue to cover for you.

Leaving work earlier than you should, and hoping your boss doesn’t notice.

Calling in sick to work, then going out for an all day pub crawl. by Siona Beht June 22, 2004

The 50%-for-breathing grading system has to be one the best techniques for teaching skiving that I can imagine.