Balboa Elementary: 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	23,841	2446.4	− 2436	10.4	× 103 / 412	2.6
4	23,843	2475.2	− 2485	−9.8	× 100 / 412	−2.4
5	23,845	2523.5	− 2528	−4.5	× 119 / 412	−1.3
6	23,847	2553.0	− 2552	1	× 90 / 412	0.2
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	22,324	2447.0	− 2436	11	× 127 / 445	3.1
4	22,325	2488.0	− 2485	3	× 106 / 445	0.7
5	22,328	2504.3	− 2528	−23.7	× 105 / 445	−5.6
6	22,330	2569.6	− 2552	17.6	× 107 / 445	4.2
Sum, rounded to a whole point						2

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,755	2419.5	− 2436	−16.5	× 110 / 444	−4.1
4	22,756	2477.0	− 2485	−8	× 125 / 444	−2.3
5	22,758	2502.5	− 2528	−25.5	× 109 / 444	−6.3
6	22,761	2529.0	− 2552	−23	× 100 / 444	−5.2
Sum, rounded to a whole point						−18

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,751	2451.3	− 2436	15.3	× 116 / 467	3.8
4	22,753	2464.6	− 2485	−20.4	× 111 / 467	−4.8
5	22,755	2521.0	− 2528	−7	× 134 / 467	−2
6	22,757	2533.5	− 2552	−18.5	× 106 / 467	−4.2
Sum, rounded to a whole point						−7

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,934	2440.1	− 2436	4.1	× 134 / 484	1.1
4	22,935	2492.6	− 2485	7.6	× 110 / 484	1.7
5	22,936	2511.0	− 2528	−17	× 114 / 484	−4
6	22,937	2544.0	− 2552	−8	× 126 / 484	−2.1
Sum, rounded to a whole point						−3

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,901	2452.3	− 2436	16.3	× 119 / 501	3.9
4	22,902	2474.0	− 2485	−11	× 134 / 501	−2.9
5	22,903	2529.8	− 2528	1.8	× 131 / 501	0.5
6	22,904	2541.8	− 2552	−10.2	× 117 / 501	−2.4
Sum, rounded to a whole point						−1

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,874	2446.8	− 2436	10.8	× 130 / 526	2.7
4	22,875	2502.2	− 2485	17.2	× 130 / 526	4.3
5	22,876	2495.6	− 2528	−32.4	× 143 / 526	−8.8
6	22,877	2542.5	− 2552	−9.5	× 123 / 526	−2.2
Sum, rounded to a whole point						−4

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,731	2419.3	− 2436	−16.7	× 130 / 418	−5.2
4	22,732	2483.5	− 2485	−1.5	× 144 / 418	−0.5
5	22,733	2532.0	− 2528	4	× 144 / 418	1.4
Sum, rounded to a whole point						−4

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	22,642	2441.2	− 2436	5.2	× 144 / 430	1.7
4	22,643	2465.4	− 2485	−19.6	× 143 / 430	−6.5
5	22,644	2508.0	− 2528	−20	× 143 / 430	−6.7
Sum, rounded to a whole point						−11

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −1, 2, −18, −7, −3, −1, −4, −4, −11 → −5.2
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: 20 · 2017→2018: 11 · 2018→2019: 4 · 2019→2022: 2 · 2022→2023: 3 · 2023→2024: 0 · 2024→2025: 7 → average 6.3
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 6.3 × 2.66 = 16.8. Upper limit 11.6, lower limit −22.

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.