Del Norte: math · Schoolio

The shaded band is this county'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	8,482	2386.4	− 2436	−49.6	× 309 / 1933	−7.9
4	8,485	2425.3	− 2485	−59.7	× 298 / 1933	−9.2
5	8,486	2453.0	− 2528	−75	× 272 / 1933	−10.6
6	8,489	2484.3	− 2552	−67.7	× 270 / 1933	−9.5
7	8,491	2494.7	− 2567	−72.3	× 258 / 1933	−9.6
8	8,492	2504.6	− 2586	−81.4	× 263 / 1933	−11.1
11	8,495	2517.6	− 2628	−110.4	× 263 / 1933	−15
Sum, rounded to a whole point						−73

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,592	2393.2	− 2436	−42.8	× 305 / 2058	−6.3
4	7,594	2432.9	− 2485	−52.1	× 328 / 2058	−8.3
5	7,597	2443.0	− 2528	−85	× 313 / 2058	−12.9
6	7,598	2478.8	− 2552	−73.2	× 292 / 2058	−10.4
7	7,600	2487.1	− 2567	−79.9	× 287 / 2058	−11.1
8	7,602	2493.7	− 2586	−92.3	× 278 / 2058	−12.5
11	7,605	2541.1	− 2628	−86.9	× 255 / 2058	−10.8
Sum, rounded to a whole point						−72

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,836	2388.1	− 2436	−47.9	× 298 / 2129	−6.7
4	7,839	2440.1	− 2485	−44.9	× 304 / 2129	−6.4
5	7,840	2445.0	− 2528	−83	× 336 / 2129	−13.1
6	7,843	2469.6	− 2552	−82.4	× 321 / 2129	−12.4
7	7,844	2489.2	− 2567	−77.8	× 297 / 2129	−10.9
8	7,846	2503.0	− 2586	−83	× 280 / 2129	−10.9
11	7,849	2522.1	− 2628	−105.9	× 293 / 2129	−14.6
Sum, rounded to a whole point						−75

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,864	2387.0	− 2436	−49	× 301 / 2116	−7
4	7,867	2442.5	− 2485	−42.5	× 306 / 2116	−6.1
5	7,868	2462.1	− 2528	−65.9	× 314 / 2116	−9.8
6	7,871	2453.9	− 2552	−98.1	× 325 / 2116	−15.1
7	7,872	2492.2	− 2567	−74.8	× 316 / 2116	−11.2
8	7,875	2495.4	− 2586	−90.6	× 295 / 2116	−12.6
11	7,876	2521.7	− 2628	−106.3	× 259 / 2116	−13
Sum, rounded to a whole point						−75

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,918	2393.8	− 2436	−42.2	× 325 / 2144	−6.4
4	7,919	2435.8	− 2485	−49.2	× 283 / 2144	−6.5
5	7,920	2455.7	− 2528	−72.3	× 293 / 2144	−9.9
6	7,921	2481.0	− 2552	−71	× 309 / 2144	−10.2
7	7,922	2486.1	− 2567	−80.9	× 333 / 2144	−12.6
8	7,923	2502.1	− 2586	−83.9	× 327 / 2144	−12.8
11	7,924	2494.7	− 2628	−133.3	× 274 / 2144	−17
Sum, rounded to a whole point						−75

2021 from sb_ca2021_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,732	2386.2	− 2436	−49.8	× 29 / 289	−5
4	7,733	2479.9	− 2485	−5.1	× 24 / 289	−0.4
5	7,734	2436.6	− 2528	−91.4	× 17 / 289	−5.4
6	7,735	2485.7	− 2552	−66.3	× 18 / 289	−4.1
7	7,736	2516.0	− 2567	−51	× 21 / 289	−3.7
8	7,737	2566.8	− 2586	−19.2	× 25 / 289	−1.7
11	7,738	2514.1	− 2628	−113.9	× 155 / 289	−61.1
Sum, rounded to a whole point						−81

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,843	2368.9	− 2436	−67.1	× 306 / 2071	−9.9
4	7,844	2411.1	− 2485	−73.9	× 304 / 2071	−10.8
5	7,845	2442.5	− 2528	−85.5	× 304 / 2071	−12.6
6	7,846	2461.0	− 2552	−91	× 304 / 2071	−13.4
7	7,847	2467.6	− 2567	−99.4	× 275 / 2071	−13.2
8	7,848	2458.3	− 2586	−127.7	× 297 / 2071	−18.3
11	7,849	2484.1	− 2628	−143.9	× 281 / 2071	−19.5
Sum, rounded to a whole point						−98

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,831	2382.0	− 2436	−54	× 316 / 2086	−8.2
4	7,832	2416.6	− 2485	−68.4	× 311 / 2086	−10.2
5	7,833	2449.1	− 2528	−78.9	× 304 / 2086	−11.5
6	7,834	2469.0	− 2552	−83	× 308 / 2086	−12.3
7	7,835	2468.8	− 2567	−98.2	× 297 / 2086	−14
8	7,836	2471.6	− 2586	−114.4	× 275 / 2086	−15.1
11	7,837	2471.7	− 2628	−156.3	× 275 / 2086	−20.6
Sum, rounded to a whole point						−92

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,775	2373.7	− 2436	−62.3	× 287 / 2066	−8.7
4	7,776	2415.3	− 2485	−69.7	× 322 / 2066	−10.9
5	7,777	2440.6	− 2528	−87.4	× 293 / 2066	−12.4
6	7,778	2464.7	− 2552	−87.3	× 295 / 2066	−12.5
7	7,779	2479.1	− 2567	−87.9	× 306 / 2066	−13
8	7,780	2476.7	− 2586	−109.3	× 295 / 2066	−15.6
11	7,781	2501.4	− 2628	−126.6	× 268 / 2066	−16.4
Sum, rounded to a whole point						−89

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,732	2372.8	− 2436	−63.2	× 291 / 2049	−9
4	7,733	2407.4	− 2485	−77.6	× 284 / 2049	−10.8
5	7,734	2446.8	− 2528	−81.2	× 316 / 2049	−12.5
6	7,735	2463.0	− 2552	−89	× 287 / 2049	−12.5
7	7,736	2493.1	− 2567	−73.9	× 297 / 2049	−10.7
8	7,737	2488.1	− 2586	−97.9	× 303 / 2049	−14.5
11	7,738	2484.7	− 2628	−143.3	× 271 / 2049	−19
Sum, rounded to a whole point						−89

2026 from sb_ca2026_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,734	2378.8	− 2436	−57.2	× 262 / 1964	−7.6
4	7,735	2417.1	− 2485	−67.9	× 289 / 1964	−10
5	7,736	2424.5	− 2528	−103.5	× 285 / 1964	−15
6	7,737	2458.9	− 2552	−93.1	× 306 / 1964	−14.5
7	7,738	2463.0	− 2567	−104	× 275 / 1964	−14.6
8	7,739	2505.8	− 2586	−80.2	× 289 / 1964	−11.8
11	7,740	2500.0	− 2628	−128	× 258 / 1964	−16.8
Sum, rounded to a whole point						−90

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −73, −72, −75, −75, −75, −81, −98, −92, −89, −89, −90 → −82.6
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 1 · 2016→2017: 3 · 2017→2018: 0 · 2018→2019: 0 · 2019→2021: 6 · 2021→2022: 17 · 2022→2023: 6 · 2023→2024: 3 · 2024→2025: 0 · 2025→2026: 1 → average 3.7
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 3.7 × 2.66 = 9.8. Upper limit −72.8, lower limit −92.4.

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 — for a county, the total across its schools. From 2014–15, 2015–16, 2016–17, 2017–18, 2018–19, 2020–21, 2021–22, 2022–23, 2023–24, 2024–25, 2025–26.