Penngrove 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	94,710	2428.4	− 2436	−7.6	× 49 / 216	−1.7
4	94,713	2453.2	− 2485	−31.8	× 52 / 216	−7.7
5	94,714	2500.3	− 2528	−27.7	× 59 / 216	−7.6
6	94,717	2547.5	− 2552	−4.5	× 56 / 216	−1.2
Sum, rounded to a whole point						−18

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	87,967	2427.8	− 2436	−8.2	× 65 / 224	−2.4
4	87,969	2469.2	− 2485	−15.8	× 52 / 224	−3.7
5	87,972	2525.3	− 2528	−2.7	× 54 / 224	−0.7
6	87,973	2551.4	− 2552	−0.6	× 53 / 224	−0.1
Sum, rounded to a whole point						−7

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	90,507	2433.0	− 2436	−3	× 52 / 219	−0.7
4	90,508	2485.7	− 2485	0.7	× 58 / 219	0.2
5	90,511	2524.9	− 2528	−3.1	× 54 / 219	−0.8
6	90,512	2559.1	− 2552	7.1	× 55 / 219	1.8
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	90,715	2470.5	− 2436	34.5	× 60 / 217	9.5
4	90,718	2481.1	− 2485	−3.9	× 47 / 217	−0.8
5	90,719	2534.1	− 2528	6.1	× 61 / 217	1.7
6	90,722	2535.5	− 2552	−16.5	× 49 / 217	−3.7
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	91,348	2462.9	− 2436	26.9	× 48 / 199	6.5
4	91,349	2505.7	− 2485	20.7	× 54 / 199	5.6
5	91,350	2519.5	− 2528	−8.5	× 46 / 199	−2
6	91,351	2546.8	− 2552	−5.2	× 51 / 199	−1.3
Sum, rounded to a whole point						9

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,602	2430.3	− 2436	−5.7	× 70 / 241	−1.7
4	91,603	2501.1	− 2485	16.1	× 58 / 241	3.9
5	91,604	2507.1	− 2528	−20.9	× 64 / 241	−5.6
6	91,605	2529.7	− 2552	−22.3	× 49 / 241	−4.5
Sum, rounded to a whole point						−8

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,492	2417.4	− 2436	−18.6	× 55 / 232	−4.4
4	91,493	2476.6	− 2485	−8.4	× 60 / 232	−2.2
5	91,494	2510.7	− 2528	−17.3	× 56 / 232	−4.2
6	91,495	2513.2	− 2552	−38.8	× 61 / 232	−10.2
Sum, rounded to a whole point						−21

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,435	2429.0	− 2436	−7	× 61 / 226	−1.9
4	91,436	2476.0	− 2485	−9	× 54 / 226	−2.2
5	91,437	2487.3	− 2528	−40.7	× 58 / 226	−10.4
6	91,438	2514.6	− 2552	−37.4	× 53 / 226	−8.8
Sum, rounded to a whole point						−23

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,133	2439.5	− 2436	3.5	× 56 / 214	0.9
4	91,134	2497.2	− 2485	12.2	× 61 / 214	3.5
5	91,135	2490.0	− 2528	−38	× 50 / 214	−8.9
6	91,136	2521.6	− 2552	−30.4	× 47 / 214	−6.7
Sum, rounded to a whole point						−11

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −18, −7, 0, 7, 9, −8, −21, −23, −11 → −8
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 11 · 2016→2017: 7 · 2017→2018: 7 · 2018→2019: 2 · 2019→2022: 17 · 2022→2023: 13 · 2023→2024: 2 · 2024→2025: 12 → average 8.9
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 8.9 × 2.66 = 23.7. Upper limit 15.7, lower limit −31.7.

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.