Del Rey Elementary: math

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.

2015 from sb_ca2015_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,904	2402.0	− 2436	−34	× 35 / 135	−8.8
4	11,907	2448.2	− 2485	−36.8	× 36 / 135	−9.8
5	11,908	2427.8	− 2528	−100.2	× 34 / 135	−25.2
6	11,911	2452.1	− 2552	−99.9	× 30 / 135	−22.2
Sum, rounded to a whole point						−66

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	10,915	2405.4	− 2436	−30.6	× 36 / 137	−8
4	10,917	2431.4	− 2485	−53.6	× 34 / 137	−13.3
5	10,918	2484.0	− 2528	−44	× 35 / 137	−11.2
6	10,920	2437.7	− 2552	−114.3	× 32 / 137	−26.7
Sum, rounded to a whole point						−59

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,245	2414.2	− 2436	−21.8	× 40 / 150	−5.8
4	11,247	2445.8	− 2485	−39.2	× 36 / 150	−9.4
5	11,249	2421.9	− 2528	−106.1	× 36 / 150	−25.5
6	11,250	2483.1	− 2552	−68.9	× 38 / 150	−17.5
Sum, rounded to a whole point						−58

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,279	2445.5	− 2436	9.5	× 32 / 137	2.2
4	11,280	2492.8	− 2485	7.8	× 37 / 137	2.1
5	11,283	2500.8	− 2528	−27.2	× 36 / 137	−7.1
6	11,284	2483.4	− 2552	−68.6	× 32 / 137	−16
Sum, rounded to a whole point						−19

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,369	2447.8	− 2436	11.8	× 36 / 144	3
4	11,370	2484.3	− 2485	−0.7	× 35 / 144	−0.2
5	11,371	2485.4	− 2528	−42.6	× 34 / 144	−10.1
6	11,372	2500.4	− 2552	−51.6	× 39 / 144	−14
Sum, rounded to a whole point						−21

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,340	2395.0	− 2436	−41	× 36 / 135	−10.9
4	11,341	2449.5	− 2485	−35.5	× 30 / 135	−7.9
5	11,342	2441.4	− 2528	−86.6	× 30 / 135	−19.2
6	11,343	2476.4	− 2552	−75.6	× 39 / 135	−21.8
Sum, rounded to a whole point						−60

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,327	2397.0	− 2436	−39	× 37 / 129	−11.2
4	11,328	2476.5	− 2485	−8.5	× 32 / 129	−2.1
5	11,329	2452.5	− 2528	−75.5	× 28 / 129	−16.4
6	11,330	2496.0	− 2552	−56	× 32 / 129	−13.9
Sum, rounded to a whole point						−44

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,282	2444.3	− 2436	8.3	× 44 / 145	2.5
4	11,283	2466.8	− 2485	−18.2	× 38 / 145	−4.8
5	11,284	2470.0	− 2528	−58	× 33 / 145	−13.2
6	11,285	2505.2	− 2552	−46.8	× 30 / 145	−9.7
Sum, rounded to a whole point						−25

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	11,215	2441.9	− 2436	5.9	× 23 / 137	1
4	11,216	2470.8	− 2485	−14.2	× 43 / 137	−4.5
5	11,217	2462.4	− 2528	−65.6	× 39 / 137	−18.7
6	11,218	2521.1	− 2552	−30.9	× 32 / 137	−7.2
Sum, rounded to a whole point						−29

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −66, −59, −58, −19, −21, −60, −44, −25, −29 → −42.3
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 7 · 2016→2017: 1 · 2017→2018: 39 · 2018→2019: 2 · 2019→2022: 39 · 2022→2023: 16 · 2023→2024: 19 · 2024→2025: 4 → average 15.9
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 15.9 × 2.66 = 42.3. Upper limit 0, lower limit −84.6.

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.

Step 3 · Free or reduced-price meals

The share of enrolled students eligible for free or reduced-price meals. From 2014–15, 2015–16, 2016–17, 2017–18, 2018–19, 2020–21, 2021–22, 2022–23, 2023–24, 2024–25, 2025–26.