Desert Willow Middle: 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
7	35,520	2448.4	− 2567	−118.6	× 310 / 590	−62.3
8	35,522	2486.6	− 2586	−99.4	× 280 / 590	−47.2
Sum, rounded to a whole point						−109

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
7	33,159	2479.6	− 2567	−87.4	× 300 / 597	−43.9
8	33,161	2464.7	− 2586	−121.3	× 297 / 597	−60.3
Sum, rounded to a whole point						−104

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,733	2454.1	− 2552	−97.9	× 58 / 625	−9.1
7	33,736	2461.2	− 2567	−105.8	× 266 / 625	−45
8	33,738	2456.0	− 2586	−130	× 301 / 625	−62.6
Sum, rounded to a whole point						−117

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,760	2447.8	− 2552	−104.2	× 293 / 834	−36.6
7	33,762	2466.2	− 2567	−100.8	× 266 / 834	−32.1
8	33,764	2440.9	− 2586	−145.1	× 275 / 834	−47.8
Sum, rounded to a whole point						−117

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,935	2443.0	− 2552	−109	× 294 / 906	−35.4
7	33,936	2445.0	− 2567	−122	× 320 / 906	−43.1
8	33,937	2471.5	− 2586	−114.5	× 292 / 906	−36.9
Sum, rounded to a whole point						−115

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,846	2425.3	− 2552	−126.7	× 282 / 865	−41.3
7	33,847	2441.2	− 2567	−125.8	× 281 / 865	−40.9
8	33,848	2450.7	− 2586	−135.3	× 302 / 865	−47.2
Sum, rounded to a whole point						−129

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,895	2432.0	− 2552	−120	× 350 / 890	−47.2
7	33,896	2450.0	− 2567	−117	× 265 / 890	−34.8
8	33,897	2435.3	− 2586	−150.7	× 275 / 890	−46.6
Sum, rounded to a whole point						−129

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,753	2412.4	− 2552	−139.6	× 343 / 950	−50.4
7	33,754	2445.6	− 2567	−121.4	× 338 / 950	−43.2
8	33,755	2442.0	− 2586	−144	× 269 / 950	−40.8
Sum, rounded to a whole point						−134

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	33,614	2411.9	− 2552	−140.1	× 233 / 890	−36.7
7	33,615	2419.9	− 2567	−147.1	× 318 / 890	−52.6
8	33,616	2453.0	− 2586	−133	× 339 / 890	−50.7
Sum, rounded to a whole point						−140

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −109, −104, −117, −117, −115, −129, −129, −134, −140 → −121.6
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 5 · 2016→2017: 13 · 2017→2018: 0 · 2018→2019: 2 · 2019→2022: 14 · 2022→2023: 0 · 2023→2024: 5 · 2024→2025: 6 → average 5.6
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 5.6 × 2.66 = 14.9. Upper limit −106.7, lower limit −136.5.

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.