Northlake Hills 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	22,022	2464.2	− 2436	28.2	× 106 / 290	10.3
4	22,024	2470.8	− 2485	−14.2	× 90 / 290	−4.4
5	22,026	2517.8	− 2528	−10.2	× 94 / 290	−3.3
Sum, rounded to a whole point						3

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	20,777	2436.1	− 2436	0.1	× 87 / 364	0
4	20,779	2501.3	− 2485	16.3	× 97 / 364	4.3
5	20,781	2481.4	− 2528	−46.6	× 87 / 364	−11.1
6	20,782	2539.6	− 2552	−12.4	× 93 / 364	−3.2
Sum, rounded to a whole point						−10

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,138	2449.1	− 2436	13.1	× 77 / 338	3
4	21,141	2489.4	− 2485	4.4	× 79 / 338	1
5	21,142	2519.8	− 2528	−8.2	× 101 / 338	−2.5
6	21,145	2537.7	− 2552	−14.3	× 81 / 338	−3.4
Sum, rounded to a whole point						−2

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,114	2469.3	− 2436	33.3	× 63 / 320	6.6
4	21,115	2517.8	− 2485	32.8	× 74 / 320	7.6
5	21,118	2538.3	− 2528	10.3	× 81 / 320	2.6
6	21,119	2538.2	− 2552	−13.8	× 102 / 320	−4.4
Sum, rounded to a whole point						12

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,288	2465.8	− 2436	29.8	× 67 / 282	7.1
4	21,289	2507.8	− 2485	22.8	× 65 / 282	5.3
5	21,290	2548.9	− 2528	20.9	× 69 / 282	5.1
6	21,291	2540.0	− 2552	−12	× 81 / 282	−3.4
Sum, rounded to a whole point						14

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,265	2437.8	− 2436	1.8	× 60 / 270	0.4
4	21,266	2462.0	− 2485	−23	× 73 / 270	−6.2
5	21,267	2515.0	− 2528	−13	× 61 / 270	−2.9
6	21,268	2518.4	− 2552	−33.6	× 76 / 270	−9.5
Sum, rounded to a whole point						−18

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,236	2441.3	− 2436	5.3	× 83 / 288	1.5
4	21,237	2469.7	− 2485	−15.3	× 63 / 288	−3.3
5	21,238	2518.3	− 2528	−9.7	× 75 / 288	−2.5
6	21,239	2527.3	− 2552	−24.7	× 67 / 288	−5.7
Sum, rounded to a whole point						−10

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,104	2470.4	− 2436	34.4	× 82 / 304	9.3
4	21,105	2491.6	− 2485	6.6	× 79 / 304	1.7
5	21,106	2487.3	− 2528	−40.7	× 60 / 304	−8
6	21,107	2548.4	− 2552	−3.6	× 83 / 304	−1
Sum, rounded to a whole point						2

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	21,019	2452.9	− 2436	16.9	× 84 / 314	4.5
4	21,020	2513.1	− 2485	28.1	× 85 / 314	7.6
5	21,021	2513.0	− 2528	−15	× 81 / 314	−3.9
6	21,022	2533.9	− 2552	−18.1	× 64 / 314	−3.7
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. 3, −10, −2, 12, 14, −18, −10, 2, 5 → −0.4
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 13 · 2016→2017: 8 · 2017→2018: 14 · 2018→2019: 2 · 2019→2022: 32 · 2022→2023: 8 · 2023→2024: 12 · 2024→2025: 3 → average 11.5
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 11.5 × 2.66 = 30.6. Upper limit 30.2, lower limit −31.

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.