Core Butte Charter: 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
3	4,228	2399.3	− 2436	−36.7	× 36 / 287	−4.6
4	4,231	2452.4	− 2485	−32.6	× 33 / 287	−3.7
5	4,232	2485.2	− 2528	−42.8	× 45 / 287	−6.7
6	4,235	2534.7	− 2552	−17.3	× 40 / 287	−2.4
7	4,236	2536.0	− 2567	−31	× 31 / 287	−3.3
8	4,239	2557.9	− 2586	−28.1	× 45 / 287	−4.4
11	4,240	2558.5	− 2628	−69.5	× 57 / 287	−13.8
Sum, rounded to a whole point						−39

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,734	2405.9	− 2436	−30.1	× 35 / 341	−3.1
4	3,737	2463.5	− 2485	−21.5	× 41 / 341	−2.6
5	3,739	2495.4	− 2528	−32.6	× 32 / 341	−3.1
6	3,740	2520.3	− 2552	−31.7	× 49 / 341	−4.6
7	3,743	2544.3	− 2567	−22.7	× 40 / 341	−2.7
8	3,744	2543.9	− 2586	−42.1	× 38 / 341	−4.7
11	3,746	2581.4	− 2628	−46.6	× 106 / 341	−14.5
Sum, rounded to a whole point						−35

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,822	2427.7	− 2436	−8.3	× 44 / 352	−1
4	3,825	2457.7	− 2485	−27.3	× 39 / 352	−3
5	3,827	2493.2	− 2528	−34.8	× 51 / 352	−5
6	3,828	2527.8	− 2552	−24.2	× 36 / 352	−2.5
7	3,831	2557.2	− 2567	−9.8	× 49 / 352	−1.4
8	3,833	2563.3	− 2586	−22.7	× 47 / 352	−3
11	3,834	2578.0	− 2628	−50	× 86 / 352	−12.2
Sum, rounded to a whole point						−28

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,824	2403.5	− 2436	−32.5	× 41 / 397	−3.4
4	3,827	2445.0	− 2485	−40	× 44 / 397	−4.4
5	3,828	2481.4	− 2528	−46.6	× 43 / 397	−5
6	3,831	2517.0	− 2552	−35	× 59 / 397	−5.2
7	3,832	2532.2	− 2567	−34.8	× 47 / 397	−4.1
8	3,835	2558.3	− 2586	−27.7	× 60 / 397	−4.2
11	3,836	2567.6	− 2628	−60.4	× 103 / 397	−15.7
Sum, rounded to a whole point						−42

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,866	2382.5	− 2436	−53.5	× 57 / 420	−7.3
4	3,867	2437.4	− 2485	−47.6	× 48 / 420	−5.4
5	3,868	2459.3	− 2528	−68.7	× 54 / 420	−8.8
6	3,869	2491.1	− 2552	−60.9	× 54 / 420	−7.8
7	3,870	2546.8	− 2567	−20.2	× 57 / 420	−2.7
8	3,871	2554.1	− 2586	−31.9	× 58 / 420	−4.4
11	3,872	2575.3	− 2628	−52.7	× 92 / 420	−11.5
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	3,710	2404.4	− 2436	−31.6	× 43 / 407	−3.3
4	3,711	2436.0	− 2485	−49	× 47 / 407	−5.7
5	3,712	2465.2	− 2528	−62.8	× 46 / 407	−7.1
6	3,713	2501.9	− 2552	−50.1	× 43 / 407	−5.3
7	3,714	2522.9	− 2567	−44.1	× 63 / 407	−6.8
8	3,715	2553.5	− 2586	−32.5	× 58 / 407	−4.6
11	3,716	2583.1	− 2628	−44.9	× 107 / 407	−11.8
Sum, rounded to a whole point						−45

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,746	2405.6	− 2436	−30.4	× 43 / 413	−3.2
4	3,747	2441.1	− 2485	−43.9	× 43 / 413	−4.6
5	3,748	2472.4	− 2528	−55.6	× 48 / 413	−6.5
6	3,749	2508.5	− 2552	−43.5	× 58 / 413	−6.1
7	3,750	2517.8	− 2567	−49.2	× 50 / 413	−6
8	3,751	2529.9	− 2586	−56.1	× 83 / 413	−11.3
11	3,752	2577.0	− 2628	−51	× 88 / 413	−10.9
Sum, rounded to a whole point						−48

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,730	2377.8	− 2436	−58.2	× 38 / 403	−5.5
4	3,731	2451.8	− 2485	−33.2	× 39 / 403	−3.2
5	3,732	2472.5	− 2528	−55.5	× 47 / 403	−6.5
6	3,733	2515.7	− 2552	−36.3	× 45 / 403	−4.1
7	3,734	2517.2	− 2567	−49.8	× 69 / 403	−8.5
8	3,735	2534.7	− 2586	−51.3	× 55 / 403	−7
11	3,736	2543.3	− 2628	−84.7	× 110 / 403	−23.1
Sum, rounded to a whole point						−58

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,696	2423.2	− 2436	−12.8	× 37 / 400	−1.2
4	3,697	2443.0	− 2485	−42	× 40 / 400	−4.2
5	3,698	2473.3	− 2528	−54.7	× 37 / 400	−5.1
6	3,699	2502.2	− 2552	−49.8	× 58 / 400	−7.2
7	3,700	2546.6	− 2567	−20.4	× 64 / 400	−3.3
8	3,701	2544.2	− 2586	−41.8	× 71 / 400	−7.4
11	3,702	2550.3	− 2628	−77.7	× 93 / 400	−18.1
Sum, rounded to a whole point						−46

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,656	2409.2	− 2436	−26.8	× 50 / 411	−3.3
4	3,657	2457.7	− 2485	−27.3	× 35 / 411	−2.3
5	3,658	2467.0	− 2528	−61	× 43 / 411	−6.4
6	3,659	2495.9	− 2552	−56.1	× 48 / 411	−6.6
7	3,660	2534.6	− 2567	−32.4	× 69 / 411	−5.4
8	3,661	2549.0	− 2586	−37	× 68 / 411	−6.1
11	3,662	2568.9	− 2628	−59.1	× 98 / 411	−14.1
Sum, rounded to a whole point						−44

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −39, −35, −28, −42, −48, −45, −48, −58, −46, −44 → −43.3
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 4 · 2016→2017: 7 · 2017→2018: 14 · 2018→2019: 6 · 2019→2021: 3 · 2021→2022: 3 · 2022→2023: 10 · 2023→2024: 12 · 2024→2025: 2 → average 6.8
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 6.8 × 2.66 = 18.1. Upper limit −25.2, lower limit −61.4.

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. From 2014–15, 2015–16, 2016–17, 2017–18, 2018–19, 2020–21, 2021–22, 2022–23, 2023–24, 2024–25, 2025–26.