API composition in 2005-06 cycle

March 2006
The API is a single-number indicator of the performance of a school’s students on state tests. Based on their API scores, schools' performance is ranked from 1 (lowest) to 10 (highest). Each spring schools receive a "Base API" between 200 and 1000 and a growth target. The following fall schools receive a "Growth API," which is based on spring test scores. APIs are calculated for the entire school and for "numerically significant subgroups" based on ethnicity, economic status, disabilities, and ability to speak English.

Scores from several tests(*) are used to compute schools' and subgroups' API scores. Different tests have different weights, and these weights have been altered as new tests have been included in the index over recent years. The weights are always the same for the Base and Growth scores within one API cycle, however. (API scores are in two-year cycles with Base API scores coming out in the first school year and Growth API scores in the second year.)

Until the 2004–05 cycle, each subject (English language arts, math, science, and social science) had a uniform weight for schools at each level (elementary, middle, and high). Now the weights can vary somewhat from school to school within the same level and API cycle, depending on which tests are taken and the percentage of students taking each test. The table below shows the weight of each component for "typical" elementary, middle, and high schools. Note: The numbers may not add up to 100% due to rounding.

Data: California Department of Education, EdSource 3/06

(*) Tests included in the API:
California Standards Tests (CST): English language arts (ELA), science, math, and social studies
Norm-referenced test (CAT/6): grades 3 & 7 only, English language arts (ELA) and math
California High School Exit Exam (CAHSEE)

The API composition in 2005-6 differs substantially from that of just a few years ago, in 2003-04.