Los Angeles Unified District Level Program: science

The shaded band is this school's normal range. If nothing about how it works changes, nearly every future year should land inside it. Zero means the typical student just meets the state standard. The small numbers under the years are how many students were tested.

Step 1 · Each year's result

For each grade tested, take the average (mean) scale score from the California Department of Education's results file, and subtract the lowest score that counts as "Standard Met" for that grade. That is the grade's distance from standard. Weight each grade by its share of the students tested, then add the grades up. Grades where the state hides the average because ten or fewer students tested are left out entirely.

2019 from cast_ca2019_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
5	8,241	172.5	− 214	−41.5	× 66 / 301	−9.1
8	8,242	376.6	− 415	−38.4	× 123 / 301	−15.7
11	8,244	579.7	− 615	−35.3	× 78 / 301	−9.1
12	8,245	573.9	− 615	−41.1	× 34 / 301	−4.6
Sum, rounded to a whole point						−39

2022 from cast_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
5	10,552	174.8	− 214	−39.2	× 32 / 183	−6.9
8	10,553	378.4	− 415	−36.6	× 45 / 183	−9
11	10,554	584.7	− 615	−30.3	× 83 / 183	−13.7
12	10,555	586.0	− 615	−29	× 23 / 183	−3.6
Sum, rounded to a whole point						−33

2023 from cast_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
5	10,648	170.5	− 214	−43.5	× 41 / 171	−10.4
8	10,649	375.7	− 415	−39.3	× 40 / 171	−9.2
11	10,651	587.9	− 615	−27.1	× 79 / 171	−12.5
12	10,652	591.7	− 615	−23.3	× 11 / 171	−1.5
Sum, rounded to a whole point						−34

2024 from cast_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
5	10,591	174.7	− 214	−39.3	× 26 / 187	−5.5
8	10,592	379.0	− 415	−36	× 77 / 187	−14.8
11	10,593	583.6	− 615	−31.4	× 84 / 187	−14.1
Sum, rounded to a whole point						−34

2025 from cast_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
5	10,598	178.9	− 214	−35.1	× 30 / 166	−6.3
8	10,599	381.6	− 415	−33.4	× 67 / 166	−13.5
11	10,601	584.5	− 615	−30.5	× 69 / 166	−12.7
Sum, rounded to a whole point						−33

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −39, −33, −34, −34, −33 → −34.6
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2019→2022: 6 · 2022→2023: 1 · 2023→2024: 0 · 2024→2025: 1 → average 2
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 2 × 2.66 = 5.3. Upper limit −29.3, lower limit −39.9.

Why 2.66? It is the standard factor from quality control, the work of Walter Shewhart and W. Edwards Deming. It turns "how much the result typically changes in a year" into "how far it can wander by chance alone".

Years with no result (no state tests were given in spring 2020) are skipped: the year-to-year change runs from the last year with a result to the next one.