Cambrian: math · Schoolio

The shaded band is this district'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	86,337	2447.4	− 2436	11.4	× 367 / 2217	1.9
4	86,339	2483.5	− 2485	−1.5	× 385 / 2217	−0.3
5	86,341	2523.4	− 2528	−4.6	× 371 / 2217	−0.8
6	86,343	2548.0	− 2552	−4	× 399 / 2217	−0.7
7	86,345	2567.1	− 2567	0.1	× 354 / 2217	0
8	86,347	2592.6	− 2586	6.6	× 341 / 2217	1
Sum, rounded to a whole point						1

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	80,130	2451.5	− 2436	15.5	× 348 / 2213	2.4
4	80,133	2484.4	− 2485	−0.6	× 362 / 2213	−0.1
5	80,134	2520.2	− 2528	−7.8	× 395 / 2213	−1.4
6	80,136	2558.5	− 2552	6.5	× 364 / 2213	1.1
7	80,139	2566.3	− 2567	−0.7	× 391 / 2213	−0.1
8	80,141	2598.6	− 2586	12.6	× 353 / 2213	2
Sum, rounded to a whole point						4

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,316	2462.4	− 2436	26.4	× 399 / 2318	4.5
4	82,318	2503.4	− 2485	18.4	× 352 / 2318	2.8
5	82,319	2510.4	− 2528	−17.6	× 372 / 2318	−2.8
6	82,322	2557.9	− 2552	5.9	× 414 / 2318	1.1
7	82,323	2583.8	− 2567	16.8	× 387 / 2318	2.8
8	82,325	2595.9	− 2586	9.9	× 394 / 2318	1.7
Sum, rounded to a whole point						10

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,519	2463.6	− 2436	27.6	× 356 / 2302	4.3
4	82,520	2517.6	− 2485	32.6	× 402 / 2302	5.7
5	82,523	2537.4	− 2528	9.4	× 358 / 2302	1.5
6	82,524	2548.6	− 2552	−3.4	× 383 / 2302	−0.6
7	82,527	2600.5	− 2567	33.5	× 410 / 2302	6
8	82,528	2625.5	− 2586	39.5	× 393 / 2302	6.7
Sum, rounded to a whole point						24

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	83,138	2476.9	− 2436	40.9	× 351 / 2211	6.5
4	83,139	2511.8	− 2485	26.8	× 337 / 2211	4.1
5	83,140	2542.3	− 2528	14.3	× 395 / 2211	2.6
6	83,141	2561.6	− 2552	9.6	× 356 / 2211	1.5
7	83,142	2592.2	− 2567	25.2	× 382 / 2211	4.4
8	83,143	2637.5	− 2586	51.5	× 390 / 2211	9.1
Sum, rounded to a whole point						28

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	83,339	2475.6	− 2436	39.6	× 320 / 2024	6.3
4	83,340	2518.3	− 2485	33.3	× 311 / 2024	5.1
5	83,341	2551.1	− 2528	23.1	× 339 / 2024	3.9
6	83,342	2541.0	− 2552	−11	× 337 / 2024	−1.8
7	83,343	2566.4	− 2567	−0.6	× 325 / 2024	−0.1
8	83,344	2612.0	− 2586	26	× 392 / 2024	5
Sum, rounded to a whole point						18

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	83,292	2476.6	− 2436	40.6	× 305 / 1968	6.3
4	83,293	2524.0	− 2485	39	× 308 / 1968	6.1
5	83,294	2546.6	− 2528	18.6	× 317 / 1968	3
6	83,295	2557.4	− 2552	5.4	× 385 / 1968	1.1
7	83,296	2582.4	− 2567	15.4	× 330 / 1968	2.6
8	83,297	2587.3	− 2586	1.3	× 323 / 1968	0.2
Sum, rounded to a whole point						19

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	83,303	2448.1	− 2436	12.1	× 287 / 1993	1.7
4	83,304	2526.4	− 2485	41.4	× 315 / 1993	6.5
5	83,305	2539.5	− 2528	11.5	× 313 / 1993	1.8
6	83,306	2554.4	− 2552	2.4	× 355 / 1993	0.4
7	83,307	2593.1	− 2567	26.1	× 392 / 1993	5.1
8	83,308	2629.7	− 2586	43.7	× 331 / 1993	7.3
Sum, rounded to a whole point						23

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,983	2465.1	− 2436	29.1	× 313 / 2046	4.5
4	82,984	2512.1	− 2485	27.1	× 293 / 2046	3.9
5	82,985	2556.0	− 2528	28	× 322 / 2046	4.4
6	82,986	2570.0	− 2552	18	× 369 / 2046	3.2
7	82,987	2603.4	− 2567	36.4	× 351 / 2046	6.2
8	82,988	2621.5	− 2586	35.5	× 398 / 2046	6.9
Sum, rounded to a whole point						29

2026 from sb_ca2026_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,794	2464.9	− 2436	28.9	× 298 / 1997	4.3
4	82,795	2499.6	− 2485	14.6	× 320 / 1997	2.3
5	82,796	2537.6	− 2528	9.6	× 298 / 1997	1.4
6	82,797	2578.6	− 2552	26.6	× 350 / 1997	4.7
7	82,798	2609.4	− 2567	42.4	× 377 / 1997	8
8	82,799	2627.5	− 2586	41.5	× 354 / 1997	7.4
Sum, rounded to a whole point						28

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. 1, 4, 10, 24, 28, 18, 19, 23, 29, 28 → 18.4
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 3 · 2016→2017: 6 · 2017→2018: 14 · 2018→2019: 4 · 2019→2022: 10 · 2022→2023: 1 · 2023→2024: 4 · 2024→2025: 6 · 2025→2026: 1 → average 5.4
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 5.4 × 2.66 = 14.4. Upper limit 32.8, lower limit 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 district, 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.

Cambrian