Tierra Buena 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	99,025	2422.9	− 2436	−13.1	× 89 / 522	−2.2
4	99,026	2455.4	− 2485	−29.6	× 84 / 522	−4.8
5	99,029	2452.3	− 2528	−75.7	× 90 / 522	−13.1
6	99,030	2512.3	− 2552	−39.7	× 88 / 522	−6.7
7	99,033	2510.2	− 2567	−56.8	× 83 / 522	−9
8	99,034	2514.6	− 2586	−71.4	× 88 / 522	−12
Sum, rounded to a whole point						−48

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,792	2417.1	− 2436	−18.9	× 85 / 507	−3.2
4	91,794	2449.1	− 2485	−35.9	× 84 / 507	−5.9
5	91,797	2457.9	− 2528	−70.1	× 86 / 507	−11.9
6	91,798	2500.0	− 2552	−52	× 87 / 507	−8.9
7	91,801	2508.3	− 2567	−58.7	× 84 / 507	−9.7
8	91,803	2509.2	− 2586	−76.8	× 81 / 507	−12.3
Sum, rounded to a whole point						−52

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	94,567	2432.3	− 2436	−3.7	× 81 / 481	−0.6
4	94,569	2450.8	− 2485	−34.2	× 79 / 481	−5.6
5	94,571	2442.2	− 2528	−85.8	× 79 / 481	−14.1
6	94,572	2509.9	− 2552	−42.1	× 79 / 481	−6.9
7	94,574	2489.7	− 2567	−77.3	× 89 / 481	−14.3
8	94,576	2510.9	− 2586	−75.1	× 74 / 481	−11.6
Sum, rounded to a whole point						−53

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	94,775	2440.4	− 2436	4.4	× 70 / 492	0.6
4	94,776	2462.1	− 2485	−22.9	× 79 / 492	−3.7
5	94,779	2455.7	− 2528	−72.3	× 81 / 492	−11.9
6	94,780	2526.9	− 2552	−25.1	× 89 / 492	−4.5
7	94,783	2499.7	− 2567	−67.3	× 82 / 492	−11.2
8	94,784	2487.4	− 2586	−98.6	× 91 / 492	−18.2
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	95,424	2458.4	− 2436	22.4	× 87 / 503	3.9
4	95,425	2486.7	− 2485	1.7	× 69 / 503	0.2
5	95,426	2465.0	− 2528	−63	× 81 / 503	−10.1
6	95,427	2512.2	− 2552	−39.8	× 96 / 503	−7.6
7	95,428	2512.1	− 2567	−54.9	× 85 / 503	−9.3
8	95,429	2522.5	− 2586	−63.5	× 85 / 503	−10.7
Sum, rounded to a whole point						−34

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	95,628	2467.9	− 2436	31.9	× 64 / 435	4.7
4	95,629	2480.9	− 2485	−4.1	× 69 / 435	−0.7
5	95,630	2482.2	− 2528	−45.8	× 63 / 435	−6.6
6	95,631	2481.0	− 2552	−71	× 85 / 435	−13.9
7	95,632	2511.9	− 2567	−55.1	× 70 / 435	−8.9
8	95,633	2502.5	− 2586	−83.5	× 84 / 435	−16.1
Sum, rounded to a whole point						−41

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	95,510	2466.8	− 2436	30.8	× 74 / 436	5.2
4	95,511	2481.3	− 2485	−3.7	× 68 / 436	−0.6
5	95,512	2500.6	− 2528	−27.4	× 74 / 436	−4.7
6	95,513	2517.8	− 2552	−34.2	× 63 / 436	−4.9
7	95,514	2494.2	− 2567	−72.8	× 87 / 436	−14.5
8	95,515	2518.1	− 2586	−67.9	× 70 / 436	−10.9
Sum, rounded to a whole point						−30

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	95,387	2474.7	− 2436	38.7	× 64 / 414	6
4	95,388	2498.5	− 2485	13.5	× 79 / 414	2.6
5	95,389	2481.8	− 2528	−46.2	× 63 / 414	−7
6	95,390	2515.9	− 2552	−36.1	× 72 / 414	−6.3
7	95,391	2521.4	− 2567	−45.6	× 62 / 414	−6.8
8	95,392	2510.6	− 2586	−75.4	× 74 / 414	−13.5
Sum, rounded to a whole point						−25

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	95,113	2498.5	− 2436	62.5	× 74 / 418	11.1
4	95,114	2485.1	− 2485	0.1	× 61 / 418	0
5	95,115	2495.8	− 2528	−32.2	× 81 / 418	−6.2
6	95,116	2513.4	− 2552	−38.6	× 67 / 418	−6.2
7	95,117	2534.4	− 2567	−32.6	× 78 / 418	−6.1
8	95,118	2539.8	− 2586	−46.2	× 57 / 418	−6.3
Sum, rounded to a whole point						−14

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −48, −52, −53, −49, −34, −41, −30, −25, −14 → −38.4
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: 1 · 2017→2018: 4 · 2018→2019: 15 · 2019→2022: 7 · 2022→2023: 11 · 2023→2024: 5 · 2024→2025: 11 → average 7.3
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 7.3 × 2.66 = 19.4. Upper limit −19, lower limit −57.8.

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.