Biggs 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	4,347	2380.4	− 2436	−55.6	× 36 / 246	−8.1
4	4,348	2399.2	− 2485	−85.8	× 29 / 246	−10.1
5	4,351	2430.8	− 2528	−97.2	× 40 / 246	−15.8
6	4,352	2435.8	− 2552	−116.2	× 35 / 246	−16.5
7	4,355	2465.1	− 2567	−101.9	× 55 / 246	−22.8
8	4,356	2478.8	− 2586	−107.2	× 51 / 246	−22.2
Sum, rounded to a whole point						−96

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,853	2364.5	− 2436	−71.5	× 31 / 248	−8.9
4	3,854	2414.8	− 2485	−70.2	× 42 / 248	−11.9
5	3,856	2419.1	− 2528	−108.9	× 27 / 248	−11.9
6	3,858	2447.3	− 2552	−104.7	× 41 / 248	−17.3
7	3,860	2476.5	− 2567	−90.5	× 53 / 248	−19.3
8	3,863	2465.0	− 2586	−121	× 54 / 248	−26.3
Sum, rounded to a whole point						−96

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,932	2361.1	− 2436	−74.9	× 29 / 220	−9.9
4	3,935	2407.2	− 2485	−77.8	× 30 / 220	−10.6
5	3,936	2435.9	− 2528	−92.1	× 37 / 220	−15.5
6	3,938	2448.7	− 2552	−103.3	× 24 / 220	−11.3
7	3,940	2484.0	− 2567	−83	× 49 / 220	−18.5
8	3,943	2477.8	− 2586	−108.2	× 51 / 220	−25.1
Sum, rounded to a whole point						−91

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,939	2379.5	− 2436	−56.5	× 37 / 223	−9.4
4	3,940	2397.0	− 2485	−88	× 30 / 223	−11.8
5	3,943	2418.8	− 2528	−109.2	× 37 / 223	−18.1
6	3,944	2462.6	− 2552	−89.4	× 34 / 223	−13.6
7	3,947	2428.3	− 2567	−138.7	× 36 / 223	−22.4
8	3,948	2470.3	− 2586	−115.7	× 49 / 223	−25.4
Sum, rounded to a whole point						−101

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,981	2383.9	− 2436	−52.1	× 36 / 222	−8.4
4	3,982	2415.0	− 2485	−70	× 38 / 222	−12
5	3,983	2408.6	− 2528	−119.4	× 27 / 222	−14.5
6	3,984	2414.7	− 2552	−137.3	× 31 / 222	−19.2
7	3,985	2492.3	− 2567	−74.7	× 48 / 222	−16.2
8	3,986	2424.4	− 2586	−161.6	× 42 / 222	−30.6
Sum, rounded to a whole point						−101

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,877	2423.9	− 2436	−12.1	× 31 / 220	−1.7
4	3,878	2374.1	− 2485	−110.9	× 35 / 220	−17.6
5	3,879	2435.9	− 2528	−92.1	× 34 / 220	−14.2
6	3,880	2447.1	− 2552	−104.9	× 36 / 220	−17.2
7	3,881	2454.3	− 2567	−112.7	× 51 / 220	−26.1
8	3,882	2411.4	− 2586	−174.6	× 33 / 220	−26.2
Sum, rounded to a whole point						−103

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,860	2404.3	− 2436	−31.7	× 32 / 216	−4.7
4	3,861	2449.1	− 2485	−35.9	× 26 / 216	−4.3
5	3,862	2411.2	− 2528	−116.8	× 36 / 216	−19.5
6	3,863	2472.8	− 2552	−79.2	× 31 / 216	−11.4
7	3,864	2470.7	− 2567	−96.3	× 41 / 216	−18.3
8	3,865	2450.8	− 2586	−135.2	× 50 / 216	−31.3
Sum, rounded to a whole point						−89

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,827	2376.3	− 2436	−59.7	× 25 / 208	−7.2
4	3,828	2403.8	− 2485	−81.2	× 34 / 208	−13.3
5	3,829	2467.4	− 2528	−60.6	× 29 / 208	−8.4
6	3,830	2406.1	− 2552	−145.9	× 46 / 208	−32.3
7	3,831	2457.2	− 2567	−109.8	× 34 / 208	−17.9
8	3,832	2471.2	− 2586	−114.8	× 40 / 208	−22.1
Sum, rounded to a whole point						−101

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	3,783	2388.8	− 2436	−47.2	× 23 / 208	−5.2
4	3,784	2421.7	− 2485	−63.3	× 29 / 208	−8.8
5	3,785	2448.3	− 2528	−79.7	× 35 / 208	−13.4
6	3,786	2492.6	− 2552	−59.4	× 30 / 208	−8.6
7	3,787	2443.4	− 2567	−123.6	× 48 / 208	−28.5
8	3,788	2493.7	− 2586	−92.3	× 43 / 208	−19.1
Sum, rounded to a whole point						−84

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −96, −96, −91, −101, −101, −103, −89, −101, −84 → −95.8
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 0 · 2016→2017: 5 · 2017→2018: 10 · 2018→2019: 0 · 2019→2022: 2 · 2022→2023: 14 · 2023→2024: 12 · 2024→2025: 17 → average 7.5
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 7.5 × 2.66 = 20. Upper limit −75.8, lower limit −115.8.

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.