Mission Bell 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	56,757	2384.6	− 2436	−51.4	× 69 / 274	−12.9
4	56,759	2424.1	− 2485	−60.9	× 56 / 274	−12.4
5	56,761	2438.3	− 2528	−89.7	× 73 / 274	−23.9
6	56,763	2472.7	− 2552	−79.3	× 76 / 274	−22
Sum, rounded to a whole point						−71

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	52,699	2403.1	− 2436	−32.9	× 65 / 265	−8.1
4	52,701	2445.7	− 2485	−39.3	× 67 / 265	−9.9
5	52,703	2432.3	− 2528	−95.7	× 55 / 265	−19.9
6	52,706	2492.6	− 2552	−59.4	× 78 / 265	−17.5
Sum, rounded to a whole point						−55

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,219	2401.0	− 2436	−35	× 65 / 250	−9.1
4	54,221	2440.9	− 2485	−44.1	× 54 / 250	−9.5
5	54,223	2444.0	− 2528	−84	× 71 / 250	−23.9
6	54,225	2473.2	− 2552	−78.8	× 60 / 250	−18.9
Sum, rounded to a whole point						−61

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,331	2368.2	− 2436	−67.8	× 61 / 246	−16.8
4	54,333	2432.0	− 2485	−53	× 59 / 246	−12.7
5	54,335	2451.2	− 2528	−76.8	× 56 / 246	−17.5
6	54,337	2492.0	− 2552	−60	× 70 / 246	−17.1
Sum, rounded to a whole point						−64

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,573	2385.6	− 2436	−50.4	× 55 / 216	−12.8
4	54,574	2449.3	− 2485	−35.7	× 49 / 216	−8.1
5	54,575	2452.1	− 2528	−75.9	× 60 / 216	−21.1
6	54,576	2492.0	− 2552	−60	× 52 / 216	−14.4
Sum, rounded to a whole point						−56

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,611	2349.7	− 2436	−86.3	× 69 / 230	−25.9
4	54,612	2422.8	− 2485	−62.2	× 48 / 230	−13
5	54,613	2397.1	− 2528	−130.9	× 60 / 230	−34.1
6	54,614	2441.6	− 2552	−110.4	× 53 / 230	−25.4
Sum, rounded to a whole point						−98

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,562	2357.0	− 2436	−79	× 53 / 227	−18.4
4	54,563	2378.1	− 2485	−106.9	× 71 / 227	−33.4
5	54,564	2403.2	− 2528	−124.8	× 47 / 227	−25.8
6	54,565	2452.6	− 2552	−99.4	× 56 / 227	−24.5
Sum, rounded to a whole point						−102

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,432	2358.8	− 2436	−77.2	× 55 / 218	−19.5
4	54,433	2400.7	− 2485	−84.3	× 53 / 218	−20.5
5	54,434	2406.8	− 2528	−121.2	× 67 / 218	−37.2
6	54,435	2464.6	− 2552	−87.4	× 43 / 218	−17.2
Sum, rounded to a whole point						−94

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	54,172	2353.5	− 2436	−82.5	× 41 / 218	−15.5
4	54,173	2397.0	− 2485	−88	× 52 / 218	−21
5	54,174	2409.3	− 2528	−118.7	× 56 / 218	−30.5
6	54,175	2428.9	− 2552	−123.1	× 69 / 218	−39
Sum, rounded to a whole point						−106

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −71, −55, −61, −64, −56, −98, −102, −94, −106 → −78.6
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 16 · 2016→2017: 6 · 2017→2018: 3 · 2018→2019: 8 · 2019→2022: 42 · 2022→2023: 4 · 2023→2024: 8 · 2024→2025: 12 → average 12.4
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 12.4 × 2.66 = 33. Upper limit −45.6, lower limit −111.6.

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.