I got an F twice in high school, and in neither case would an extra 12 weeks have made a difference.
Failing grades don't catch students or teachers by surprise. They know there's a problem well before the end of the term. I think these extentions will be wasted in most cases.
Agreed. My 7th grade class this year is a wonder to behold. We've gotten back their standardized tests and it's the first class I've ever had where all but four are within 4 pts of 100, (not an IQ, just sounds like it.

) The 'low' was 89, the other three were above 104, the highest 128.
Yet, they are the worst class about doing assignments and their tests are abysmal. I actually laid out $50 to be able to post quizzes and activities so they could review online from home. This morning I basically laid out how to do their essays, organizational wise. I told them the topics, but not the actual way they'd have to approach the topic, (compare and contrast, analyze, predict...). I gave them time to use their text to write a 'practice essay.'
Graded them during my free period. High 88%, Low 38%, most are in 70's.
Class as a whole:
Class Average Statistics
High 93.3%
Low 59.34%
Mean 78.04%
Median 80%
Our grading scale (tough)
Grading Scale
A+ 100 C 79
A 96 C- 77
A- 93 D+ 75
B+ 91 D 72
B 88 D- 70
B- 85 F 0
C+ 83
Their 'scores' are higher than their performance, as I grade homework as full points, IF they correct mistakes and add important missing information. About every 5 weeks, I collect their notebooks and grade those based upon taking notes and making corrections to their homework. Their highest notebook grade replaces their lowest test grade, IF it's better.
Are they being 'coddled?' Indeed. Yet by the time I get them in middle school, they are so conditioned to 'working with a group' and being given certain 'projects' to finish as a group, that we just are attempting to teach, while getting them ready for high school.
I had one kid today say, "You keep giving us chapter tests, why not give us just 'section tests', it's too much information?" I explained that was the reason to keep their section quizzes and study them before the test. His reply, "It's too much work."