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I'm not sure this collection of anecdotes will be news to someone who has been following education policy for a while but I do think the topic is important. Wit

I'm not sure this collection of anecdotes will be news to someone who has been following education policy for a while but I do think the topic is important. With the importance of the topic in mind, I'll suggest here some better things to read on improving education. http://stuff.mit.edu:8001/afs/athena/course/6/6.969/OldFiles/www/readings/ma-review.pdf http://stuff.mit.edu:8001/afs/athena/course/6/6.969/OldFiles... (review of a very important book that essentially every parent in the English-speaking world ought to read) http://hanushek.stanford.edu/publications/teacher-quality http://hanushek.stanford.edu/publications/teacher-quality (a collection of articles on teacher quality by an experienced education policy researcher) http://educationnext.org/ http://educationnext.org/ (website of a journal on education policy issues)

Alex3917 14y ago
For what it's worth Hanushek is most famous for his theory that a student having a teacher in the 85th percentile or better for test score improvement for five years in a row would be enough to close the gap between low-SES and high-SES kids, a theory which has been soundly disproven. I have no idea about the quality of his other research, but I'd tread with extreme caution there. edit: C.f. The Death and Life of the Great American School System by Diane Ravitch, the paperback edition, esp. chapters 6 - 9 and the epilogue.
- tokenadult 14y ago
  I'd have to look up the reference you kindly shared, but I sure hope Ravitch had help with her mathematics in that analysis, as she is the person who doubts the general usefulness of even beginning algebra as a high school graduation requirement. (Her higher education was in history, not any quantitative subject as Hanushek's was.)
  - Alex3917 14y ago
    She is citing other studies that attack Hanushek's analysis, but she isn't citing any mathematical arguments that she created herself. There are a number of problems with Hanushek's argument, among them: - The ratings are completely unstable, so a teacher who is in the bottom 20% one year has a pretty good chance of being in the top 20% the next year. - Hanushek doesn't account for forgetfulness when evaluating the differences between teachers. So if you retest the students on the same material two years later, it turns out that the difference between a great teacher and a mediacre teacher is only about 1 / 8th as much as Hanushek had supposed. And the teachers that do the best in the short term (at the end of the school year) have little correlation with the teachers that are actually the most effective in terms of getting kids to know the most after two years, which is what is actually important. - Even if the teacher ratings were stable, which they aren't, they're not on an interval scale, meaning that the comparisons between different teachers are largely meaningless. - Students aren't assigned randomly to classrooms, and the differences between their abilities and backgrounds can't fully be corrected for for various reasons. (One of which being that again the tests are not on an interval scale.) - In order for the VAM to become at least fairly stable it takes about 7 years, by which point about 60% of teachers have already been fired or quit anyway. - VAM only works for math and literacy and not the other subjects that aren't tested. - The VAM ratings are extremely test specific, and if you give a different test of the exact same material to the same kids then the teachers that are 'effective' or 'ineffective' are often wildly different. - VAM only works if you have data for kids from the previous year. However the data tends to be missing for about a third of kids, especially in low-SES communities where people move around much more, which means that VAM is much less accurate in minority communities due to having less data to draw from and therefor less statistical power. Which means that it's effectively firing/disciplining/rewarding teachers at random in these communities, and therefor discouraging good teachers from teaching there. There are other issues too, I'm happy to email you my notes if you'd like, which are mostly from the sources that Ravitch cites and not from Ravitch herself. (The sources are mostly things like Department of Education studies.)

Alex3917 14y ago

For what it's worth Hanushek is most famous for his theory that a student having a teacher in the 85th percentile or better for test score improvement for five years in a row would be enough to close the gap between low-SES and high-SES kids, a theory which has been soundly disproven. I have no idea about the quality of his other research, but I'd tread with extreme caution there. edit: C.f. The Death and Life of the Great American School System by Diane Ravitch, the paperback edition, esp. chapters 6 - 9 and the epilogue.

tokenadult 14y ago
I'd have to look up the reference you kindly shared, but I sure hope Ravitch had help with her mathematics in that analysis, as she is the person who doubts the general usefulness of even beginning algebra as a high school graduation requirement. (Her higher education was in history, not any quantitative subject as Hanushek's was.)
- Alex3917 14y ago
  She is citing other studies that attack Hanushek's analysis, but she isn't citing any mathematical arguments that she created herself. There are a number of problems with Hanushek's argument, among them: - The ratings are completely unstable, so a teacher who is in the bottom 20% one year has a pretty good chance of being in the top 20% the next year. - Hanushek doesn't account for forgetfulness when evaluating the differences between teachers. So if you retest the students on the same material two years later, it turns out that the difference between a great teacher and a mediacre teacher is only about 1 / 8th as much as Hanushek had supposed. And the teachers that do the best in the short term (at the end of the school year) have little correlation with the teachers that are actually the most effective in terms of getting kids to know the most after two years, which is what is actually important. - Even if the teacher ratings were stable, which they aren't, they're not on an interval scale, meaning that the comparisons between different teachers are largely meaningless. - Students aren't assigned randomly to classrooms, and the differences between their abilities and backgrounds can't fully be corrected for for various reasons. (One of which being that again the tests are not on an interval scale.) - In order for the VAM to become at least fairly stable it takes about 7 years, by which point about 60% of teachers have already been fired or quit anyway. - VAM only works for math and literacy and not the other subjects that aren't tested. - The VAM ratings are extremely test specific, and if you give a different test of the exact same material to the same kids then the teachers that are 'effective' or 'ineffective' are often wildly different. - VAM only works if you have data for kids from the previous year. However the data tends to be missing for about a third of kids, especially in low-SES communities where people move around much more, which means that VAM is much less accurate in minority communities due to having less data to draw from and therefor less statistical power. Which means that it's effectively firing/disciplining/rewarding teachers at random in these communities, and therefor discouraging good teachers from teaching there. There are other issues too, I'm happy to email you my notes if you'd like, which are mostly from the sources that Ravitch cites and not from Ravitch herself. (The sources are mostly things like Department of Education studies.)