Today, another piece of evidence that teachers continue to get better with experience. Helen Ladd and Lucy Sorensen offer new findings, based on middle school teachers in North Carolina, suggesting that learning-on-the-job continues for an extended period, perhaps a decade or so.
Ladd and Sorensen put together a graph of math results for teachers of different levels of experience.
You can see that more experienced teachers produce bigger gains. What’s new is that the gains seem to keep getting better at least to 7 or 8 years and maybe for a good bit longer. The estimates still suggest the biggest gain comes after a single year of experience with a further big gain in the second year. Something like half the gain from experience happens in those first two years, but that still means that teachers continue to improve gradually for another decade or more.
By the way, Ladd and Sorensen find the pattern is similar in teaching reading, although less dramatic.