The College Board has released the 2015 AP Data (http://research.collegeboard.org/programs/ap/data/participation/ap-2015), which contains the following information about AP Physics 1:
– I’d expected that a lot of younger kids taking it would have been part of the cause of low scores, because our HS taught it to a fairly large number of 9th graders. But, that does not seem to be the case: (https://secure-media.collegeboard.org/digitalServices/pdf/research/2015/Program-Summary-Report-2015.pdf)
9th grade: 1,828 students
10th grade: 10,440
11th grade: 95,719
12th grade: 59,307
<9th grade: 66
– Mean score was 2.32. Lowest mean score, as is obvious from the previously published distribution. Standard deviation was 1.19. (https://secure-media.collegeboard.org/digitalServices/pdf/research/2015/Student-Score-Distributions-2015.pdf)
– 6776 schools offered AP Physics 1, up from 5797 schools that offered AP Physics B in it’s last year. So, perhaps ~1000 new AP Physics teachers?