Peabody Charter: 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	85,564	2431.7	− 2436	−4.3	× 99 / 424	−1
4	85,565	2509.3	− 2485	24.3	× 106 / 424	6.1
5	85,568	2543.7	− 2528	15.7	× 109 / 424	4
6	85,569	2559.2	− 2552	7.2	× 110 / 424	1.9
Sum, rounded to a whole point						11

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	79,377	2445.9	− 2436	9.9	× 102 / 424	2.4
4	79,379	2468.1	− 2485	−16.9	× 110 / 424	−4.4
5	79,381	2543.2	− 2528	15.2	× 105 / 424	3.8
6	79,383	2579.8	− 2552	27.8	× 107 / 424	7
Sum, rounded to a whole point						9

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	81,546	2445.1	− 2436	9.1	× 104 / 425	2.2
4	81,548	2479.2	− 2485	−5.8	× 106 / 425	−1.4
5	81,549	2504.4	− 2528	−23.6	× 111 / 425	−6.2
6	81,551	2573.1	− 2552	21.1	× 104 / 425	5.2
Sum, rounded to a whole point						0

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	81,737	2432.9	− 2436	−3.1	× 108 / 424	−0.8
4	81,738	2476.8	− 2485	−8.2	× 107 / 424	−2.1
5	81,741	2510.5	− 2528	−17.5	× 105 / 424	−4.3
6	81,742	2552.0	− 2552	0	× 104 / 424	0
Sum, rounded to a whole point						−7

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,256	2452.7	− 2436	16.7	× 111 / 431	4.3
4	82,257	2471.1	− 2485	−13.9	× 108 / 431	−3.5
5	82,258	2509.7	− 2528	−18.3	× 106 / 431	−4.5
6	82,259	2555.2	− 2552	3.2	× 106 / 431	0.8
Sum, rounded to a whole point						−3

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,463	2487.4	− 2436	51.4	× 108 / 418	13.3
4	82,464	2505.7	− 2485	20.7	× 106 / 418	5.2
5	82,465	2517.6	− 2528	−10.4	× 98 / 418	−2.4
6	82,466	2563.3	− 2552	11.3	× 106 / 418	2.9
Sum, rounded to a whole point						19

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,429	2502.4	− 2436	66.4	× 109 / 426	17
4	82,430	2518.5	− 2485	33.5	× 112 / 426	8.8
5	82,431	2520.5	− 2528	−7.5	× 107 / 426	−1.9
6	82,432	2550.5	− 2552	−1.5	× 98 / 426	−0.3
Sum, rounded to a whole point						24

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,443	2466.3	− 2436	30.3	× 104 / 436	7.2
4	82,444	2524.9	− 2485	39.9	× 112 / 436	10.2
5	82,445	2543.0	− 2528	15	× 110 / 436	3.8
6	82,446	2580.6	− 2552	28.6	× 110 / 436	7.2
Sum, rounded to a whole point						28

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	82,121	2463.0	− 2436	27	× 110 / 430	6.9
4	82,122	2513.2	− 2485	28.2	× 102 / 430	6.7
5	82,123	2551.7	− 2528	23.7	× 111 / 430	6.1
6	82,124	2596.3	− 2552	44.3	× 107 / 430	11
Sum, rounded to a whole point						31

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. 11, 9, 0, −7, −3, 19, 24, 28, 31 → 12.4
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 2 · 2016→2017: 9 · 2017→2018: 7 · 2018→2019: 4 · 2019→2022: 22 · 2022→2023: 5 · 2023→2024: 4 · 2024→2025: 3 → average 7
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 7 × 2.66 = 18.6. Upper limit 31, lower limit −6.2.

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.