Richard Henry Dana 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	48,617	2382.5	− 2436	−53.5	× 51 / 149	−18.3
4	48,618	2467.3	− 2485	−17.7	× 49 / 149	−5.8
5	48,621	2488.0	− 2528	−40	× 49 / 149	−13.2
Sum, rounded to a whole point						−37

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	45,209	2405.6	− 2436	−30.4	× 46 / 143	−9.8
4	45,211	2423.5	− 2485	−61.5	× 48 / 143	−20.6
5	45,214	2502.1	− 2528	−25.9	× 49 / 143	−8.9
Sum, rounded to a whole point						−39

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,420	2378.2	− 2436	−57.8	× 47 / 135	−20.1
4	46,421	2433.8	− 2485	−51.2	× 43 / 135	−16.3
5	46,424	2447.0	− 2528	−81	× 45 / 135	−27
Sum, rounded to a whole point						−63

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,429	2401.0	− 2436	−35	× 37 / 122	−10.6
4	46,431	2438.1	− 2485	−46.9	× 44 / 122	−16.9
5	46,433	2464.2	− 2528	−63.8	× 41 / 122	−21.4
Sum, rounded to a whole point						−49

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,612	2434.7	− 2436	−1.3	× 29 / 101	−0.4
4	46,613	2452.4	− 2485	−32.6	× 34 / 101	−11
5	46,614	2480.2	− 2528	−47.8	× 38 / 101	−18
Sum, rounded to a whole point						−29

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,448	2408.9	− 2436	−27.1	× 26 / 82	−8.6
4	46,449	2433.8	− 2485	−51.2	× 29 / 82	−18.1
5	46,450	2482.4	− 2528	−45.6	× 27 / 82	−15
Sum, rounded to a whole point						−42

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,438	2441.8	− 2436	5.8	× 53 / 110	2.8
4	46,439	2464.3	− 2485	−20.7	× 27 / 110	−5.1
5	46,440	2438.0	− 2528	−90	× 30 / 110	−24.5
Sum, rounded to a whole point						−27

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,291	2431.0	− 2436	−5	× 50 / 127	−2
4	46,292	2485.4	− 2485	0.4	× 50 / 127	0.2
5	46,293	2456.2	− 2528	−71.8	× 27 / 127	−15.3
Sum, rounded to a whole point						−17

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	46,051	2467.3	− 2436	31.3	× 58 / 155	11.7
4	46,052	2492.1	− 2485	7.1	× 49 / 155	2.2
5	46,053	2498.4	− 2528	−29.6	× 48 / 155	−9.2
Sum, rounded to a whole point						5

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −37, −39, −63, −49, −29, −42, −27, −17, 5 → −33.1
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 2 · 2016→2017: 24 · 2017→2018: 14 · 2018→2019: 20 · 2019→2022: 13 · 2022→2023: 15 · 2023→2024: 10 · 2024→2025: 22 → average 15
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 15 × 2.66 = 39.9. Upper limit 6.8, lower limit −73.

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.