Lassen: 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	19,681	2385.8	− 2436	−50.2	× 316 / 2239	−7.1
4	19,684	2444.8	− 2485	−40.2	× 290 / 2239	−5.2
5	19,685	2467.7	− 2528	−60.3	× 325 / 2239	−8.8
6	19,688	2492.9	− 2552	−59.1	× 293 / 2239	−7.7
7	19,689	2507.8	− 2567	−59.2	× 301 / 2239	−8
8	19,692	2533.3	− 2586	−52.7	× 340 / 2239	−8
11	19,693	2517.4	− 2628	−110.6	× 374 / 2239	−18.5
Sum, rounded to a whole point						−63

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	18,695	2407.5	− 2436	−28.5	× 310 / 2220	−4
4	18,698	2445.8	− 2485	−39.2	× 314 / 2220	−5.5
5	18,700	2475.9	− 2528	−52.1	× 293 / 2220	−6.9
6	18,701	2492.1	− 2552	−59.9	× 326 / 2220	−8.8
7	18,704	2512.1	− 2567	−54.9	× 302 / 2220	−7.5
8	18,705	2540.7	− 2586	−45.3	× 306 / 2220	−6.2
11	18,708	2530.8	− 2628	−97.2	× 369 / 2220	−16.2
Sum, rounded to a whole point						−55

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,030	2401.6	− 2436	−34.4	× 302 / 2117	−4.9
4	19,033	2457.5	− 2485	−27.5	× 296 / 2117	−3.8
5	19,034	2464.9	− 2528	−63.1	× 323 / 2117	−9.6
6	19,036	2491.5	− 2552	−60.5	× 287 / 2117	−8.2
7	19,038	2505.2	− 2567	−61.8	× 321 / 2117	−9.4
8	19,040	2531.1	− 2586	−54.9	× 288 / 2117	−7.5
11	19,043	2542.3	− 2628	−85.7	× 300 / 2117	−12.1
Sum, rounded to a whole point						−56

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,036	2414.4	− 2436	−21.6	× 275 / 1992	−3
4	19,039	2456.8	− 2485	−28.2	× 295 / 1992	−4.2
5	19,040	2468.8	− 2528	−59.2	× 280 / 1992	−8.3
6	19,043	2483.4	− 2552	−68.6	× 289 / 1992	−10
7	19,044	2514.7	− 2567	−52.3	× 278 / 1992	−7.3
8	19,047	2520.4	− 2586	−65.6	× 312 / 1992	−10.3
11	19,048	2529.3	− 2628	−98.7	× 263 / 1992	−13
Sum, rounded to a whole point						−56

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,195	2403.8	− 2436	−32.2	× 315 / 2003	−5.1
4	19,196	2465.3	− 2485	−19.7	× 291 / 2003	−2.9
5	19,197	2482.2	− 2528	−45.8	× 294 / 2003	−6.7
6	19,198	2495.5	− 2552	−56.5	× 287 / 2003	−8.1
7	19,199	2514.0	− 2567	−53	× 288 / 2003	−7.6
8	19,200	2534.2	− 2586	−51.8	× 272 / 2003	−7
11	19,201	2546.0	− 2628	−82	× 256 / 2003	−10.5
Sum, rounded to a whole point						−48

2021 from sb_ca2021_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	18,724	2392.8	− 2436	−43.2	× 269 / 1963	−5.9
4	18,725	2430.4	− 2485	−54.6	× 257 / 1963	−7.1
5	18,726	2452.3	− 2528	−75.7	× 316 / 1963	−12.2
6	18,727	2483.0	− 2552	−69	× 265 / 1963	−9.3
7	18,728	2499.6	− 2567	−67.4	× 297 / 1963	−10.2
8	18,729	2530.0	− 2586	−56	× 272 / 1963	−7.8
11	18,730	2500.1	− 2628	−127.9	× 287 / 1963	−18.7
Sum, rounded to a whole point						−71

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,250	2380.3	− 2436	−55.7	× 275 / 1924	−8
4	19,251	2442.3	− 2485	−42.7	× 272 / 1924	−6
5	19,252	2455.3	− 2528	−72.7	× 255 / 1924	−9.6
6	19,253	2471.8	− 2552	−80.2	× 311 / 1924	−13
7	19,254	2492.4	− 2567	−74.6	× 262 / 1924	−10.2
8	19,255	2524.3	− 2586	−61.7	× 294 / 1924	−9.4
11	19,256	2495.5	− 2628	−132.5	× 255 / 1924	−17.6
Sum, rounded to a whole point						−74

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,197	2390.2	− 2436	−45.8	× 269 / 1893	−6.5
4	19,198	2429.8	− 2485	−55.2	× 272 / 1893	−7.9
5	19,199	2468.2	− 2528	−59.8	× 265 / 1893	−8.4
6	19,200	2477.7	− 2552	−74.3	× 240 / 1893	−9.4
7	19,201	2488.8	− 2567	−78.2	× 314 / 1893	−13
8	19,202	2493.2	− 2586	−92.8	× 266 / 1893	−13
11	19,203	2502.1	− 2628	−125.9	× 267 / 1893	−17.8
Sum, rounded to a whole point						−76

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,141	2394.3	− 2436	−41.7	× 279 / 1874	−6.2
4	19,142	2423.0	− 2485	−62	× 266 / 1874	−8.8
5	19,143	2450.7	− 2528	−77.3	× 273 / 1874	−11.3
6	19,144	2470.6	− 2552	−81.4	× 264 / 1874	−11.5
7	19,145	2497.2	− 2567	−69.8	× 244 / 1874	−9.1
8	19,146	2500.7	− 2586	−85.3	× 299 / 1874	−13.6
11	19,147	2515.2	− 2628	−112.8	× 249 / 1874	−15
Sum, rounded to a whole point						−75

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,126	2402.3	− 2436	−33.7	× 266 / 1856	−4.8
4	19,127	2436.6	− 2485	−48.4	× 271 / 1856	−7.1
5	19,128	2455.7	− 2528	−72.3	× 266 / 1856	−10.4
6	19,129	2479.1	− 2552	−72.9	× 265 / 1856	−10.4
7	19,130	2501.6	− 2567	−65.4	× 267 / 1856	−9.4
8	19,131	2512.5	− 2586	−73.5	× 243 / 1856	−9.6
11	19,132	2510.6	− 2628	−117.4	× 278 / 1856	−17.6
Sum, rounded to a whole point						−69

2026 from sb_ca2026_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,147	2390.5	− 2436	−45.5	× 267 / 1840	−6.6
4	19,148	2436.9	− 2485	−48.1	× 267 / 1840	−7
5	19,149	2453.1	− 2528	−74.9	× 259 / 1840	−10.5
6	19,150	2480.3	− 2552	−71.7	× 269 / 1840	−10.5
7	19,151	2494.3	− 2567	−72.7	× 257 / 1840	−10.2
8	19,152	2505.0	− 2586	−81	× 269 / 1840	−11.8
11	19,153	2507.7	− 2628	−120.3	× 252 / 1840	−16.5
Sum, rounded to a whole point						−73

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −63, −55, −56, −56, −48, −71, −74, −76, −75, −69, −73 → −65.1
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 8 · 2016→2017: 1 · 2017→2018: 0 · 2018→2019: 8 · 2019→2021: 23 · 2021→2022: 3 · 2022→2023: 2 · 2023→2024: 1 · 2024→2025: 6 · 2025→2026: 4 → 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 −50.2, lower limit −80.

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.