Sonoma County Office of Education: math

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
4	93,772	2343.5	− 2485	−141.5	× 10 / 93	−15.2
6	93,777	2335.9	− 2552	−216.1	× 11 / 93	−25.6
7	93,778	2374.2	− 2567	−192.8	× 11 / 93	−22.8
8	93,781	2397.9	− 2586	−188.1	× 17 / 93	−34.4
11	93,782	2394.5	− 2628	−233.5	× 44 / 93	−110.5
Sum, rounded to a whole point						−208

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
7	87,139	2350.4	− 2567	−216.6	× 13 / 57	−49.4
8	87,142	2334.8	− 2586	−251.2	× 18 / 57	−79.3
11	87,143	2454.0	− 2628	−174	× 26 / 57	−79.4
Sum, rounded to a whole point						−208

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	89,580	2368.0	− 2552	−184	× 16 / 50	−58.9
11	89,587	2422.2	− 2628	−205.8	× 34 / 50	−139.9
Sum, rounded to a whole point						−199

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
7	89,794	2387.2	− 2567	−179.8	× 11 / 68	−29.1
8	89,795	2356.3	− 2586	−229.7	× 17 / 68	−57.4
11	89,798	2427.4	− 2628	−200.6	× 40 / 68	−118
Sum, rounded to a whole point						−205

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
6	90,420	2345.7	− 2552	−206.3	× 12 / 103	−24
7	90,421	2416.6	− 2567	−150.4	× 14 / 103	−20.4
8	90,422	2392.4	− 2586	−193.6	× 35 / 103	−65.8
11	90,423	2396.7	− 2628	−231.3	× 42 / 103	−94.3
Sum, rounded to a whole point						−205

2021 from sb_ca2021_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
11	88,589	2462.2	− 2628	−165.8	× 16 / 16	−165.8
Sum, rounded to a whole point						−166

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
7	90,679	2357.9	− 2567	−209.1	× 14 / 42	−69.7
8	90,680	2405.4	− 2586	−180.6	× 14 / 42	−60.2
11	90,681	2420.5	− 2628	−207.5	× 14 / 42	−69.2
Sum, rounded to a whole point						−199

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
8	90,582	2327.2	− 2586	−258.8	× 21 / 49	−110.9
11	90,583	2378.7	− 2628	−249.3	× 28 / 49	−142.5
Sum, rounded to a whole point						−253

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
8	90,511	2401.9	− 2586	−184.1	× 16 / 39	−75.5
11	90,512	2418.3	− 2628	−209.7	× 23 / 39	−123.7
Sum, rounded to a whole point						−199

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
8	90,189	2415.9	− 2586	−170.1	× 13 / 39	−56.7
11	90,190	2396.3	− 2628	−231.7	× 26 / 39	−154.5
Sum, rounded to a whole point						−211

2026 from sb_ca2026_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
11	89,861	2416.8	− 2628	−211.2	× 22 / 22	−211.2
Sum, rounded to a whole point						−211

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −208, −208, −199, −205, −205, −166, −199, −253, −199, −211, −211 → −205.8
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 0 · 2016→2017: 9 · 2017→2018: 6 · 2018→2019: 0 · 2019→2021: 39 · 2021→2022: 33 · 2022→2023: 54 · 2023→2024: 54 · 2024→2025: 12 · 2025→2026: 0 → average 20.7
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 20.7 × 2.66 = 55.1. Upper limit −150.7, lower limit −260.9.

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.

Sonoma County Office of Education