Martin Luther King, Jr. 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	7,835	2328.0	− 2436	−108	× 67 / 239	−30.3
4	7,836	2381.6	− 2485	−103.4	× 66 / 239	−28.6
5	7,839	2398.0	− 2528	−130	× 58 / 239	−31.5
6	7,841	2452.8	− 2552	−99.2	× 48 / 239	−19.9
Sum, rounded to a whole point						−110

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,018	2373.4	− 2436	−62.6	× 61 / 237	−16.1
4	7,021	2369.8	− 2485	−115.2	× 62 / 237	−30.1
5	7,022	2425.7	− 2528	−102.3	× 63 / 237	−27.2
6	7,025	2410.3	− 2552	−141.7	× 51 / 237	−30.5
Sum, rounded to a whole point						−104

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,230	2350.1	− 2436	−85.9	× 71 / 250	−24.4
4	7,233	2378.0	− 2485	−107	× 64 / 250	−27.4
5	7,234	2355.1	− 2528	−172.9	× 59 / 250	−40.8
6	7,237	2384.2	− 2552	−167.8	× 56 / 250	−37.6
Sum, rounded to a whole point						−130

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,249	2331.0	− 2436	−105	× 67 / 239	−29.4
4	7,251	2347.3	− 2485	−137.7	× 63 / 239	−36.3
5	7,253	2346.7	− 2528	−181.3	× 58 / 239	−44
6	7,255	2358.2	− 2552	−193.8	× 51 / 239	−41.4
Sum, rounded to a whole point						−151

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,299	2327.5	− 2436	−108.5	× 69 / 249	−30.1
4	7,300	2364.8	− 2485	−120.2	× 66 / 249	−31.9
5	7,301	2374.2	− 2528	−153.8	× 54 / 249	−33.4
6	7,302	2408.6	− 2552	−143.4	× 60 / 249	−34.6
Sum, rounded to a whole point						−130

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,244	2331.3	− 2436	−104.7	× 56 / 200	−29.3
4	7,245	2358.7	− 2485	−126.3	× 53 / 200	−33.5
5	7,246	2369.2	− 2528	−158.8	× 50 / 200	−39.7
6	7,247	2381.2	− 2552	−170.8	× 41 / 200	−35
Sum, rounded to a whole point						−137

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,232	2322.8	− 2436	−113.2	× 56 / 205	−30.9
4	7,233	2359.0	− 2485	−126	× 57 / 205	−35
5	7,234	2352.3	− 2528	−175.7	× 51 / 205	−43.7
6	7,235	2368.1	− 2552	−183.9	× 41 / 205	−36.8
Sum, rounded to a whole point						−146

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,179	2328.8	− 2436	−107.2	× 63 / 234	−28.9
4	7,180	2359.7	− 2485	−125.3	× 57 / 234	−30.5
5	7,181	2368.5	− 2528	−159.5	× 55 / 234	−37.5
6	7,182	2388.5	− 2552	−163.5	× 59 / 234	−41.2
Sum, rounded to a whole point						−138

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	7,139	2327.6	− 2436	−108.4	× 42 / 212	−21.5
4	7,140	2373.6	− 2485	−111.4	× 59 / 212	−31
5	7,141	2373.3	− 2528	−154.7	× 55 / 212	−40.1
6	7,142	2385.9	− 2552	−166.1	× 56 / 212	−43.9
Sum, rounded to a whole point						−136

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −110, −104, −130, −151, −130, −137, −146, −138, −136 → −131.3
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 6 · 2016→2017: 26 · 2017→2018: 21 · 2018→2019: 21 · 2019→2022: 7 · 2022→2023: 9 · 2023→2024: 8 · 2024→2025: 2 → average 12.5
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 12.5 × 2.66 = 33.3. Upper limit −98, lower limit −164.6.

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.