An interesting new study came out that showed offering teachers bonuses of up to $15,000 doesn't raise student performance. I can think of a couple of explanations.
First, it's possible that the type of people who go into teaching--especially in tough neighborhoods-- are the type of people who aren't motivated by money. For these people, teaching is a calling and not just a vocation. They would work just as hard regardless of whether bonuses are offered. In other words, the lure of extra cash didn't motivate them to do anything they wouldn't already for their students.
Second, it's possible that the circumstances these teachers work under defy solutions that they can readily implement in the classroom. In many districts, students come to school years behind where they should be in their subjects, and with all kinds of issues confronting them ranging from hunger, to fatherlessness, to crime. Working against these enormous obstacles, even teachers motivated to do extra work by the money are simply powerless to do anything much.
I don't put much stock in this explanation. Numerous studies have shown that a good teacher can make a difference in even the toughest situations. Here is one. So if teachers can make such a difference, then why wouldn't motivating people to be good teachers affect student achievement?
Third, and on a related note, it might be the case that teachers in certain situations lack the means to become better. In order to produce results, they need more experience and training. Perhaps they aren't receiving the guidance and mentorship they need to improve even though they really want to so they can earn the bonus. Or perhaps, they simply need more time in the classroom to develop important skills.
For example, offering a rookie NBA player a bonus of $10 million for scoring 30 points a game might give him an incentive to train harder and try harder. But on some level, he needs to develop as a player and more experience before he can score 30 points a game. So even though he has a greater incentive to score than he did before, he doesn't yet have the means. To test this reasoning, it would be interesting to see what happens when teachers all have at least five years of experience and easy access to training and mentorship resources. Would test scores rise then for teachers who are offered the bonus?
One important question is whether bonuses would draw additional talent who might not have considered teaching before. Such people might be more likely to become engineers or lawyers to make more money. It stands to reason that paying out larger salaries to these individuals might make teaching a more competitive option. My hunch would be that even larger bonuses than offered in this study might be necessary to lure such people since engineers and lawyers can make six figures. Whatever the case, it is certainly worth investigating ways to get more people to consider teaching.