River Montessori Elementary Charter: english

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	94,601	2439.6	− 2432	7.6	× 23 / 89	2
4	94,602	2457.9	− 2473	−15.1	× 27 / 89	−4.6
5	94,605	2540.2	− 2502	38.2	× 17 / 89	7.3
6	94,606	2581.3	− 2531	50.3	× 22 / 89	12.4
Sum, rounded to a whole point						17

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	87,843	2411.3	− 2432	−20.7	× 34 / 69	−10.2
4	87,846	2468.7	− 2473	−4.3	× 16 / 69	−1
5	87,847	2503.4	− 2502	1.4	× 19 / 69	0.4
Sum, rounded to a whole point						−11

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	90,372	2408.7	− 2432	−23.3	× 21 / 47	−10.4
4	90,374	2446.3	− 2473	−26.7	× 26 / 47	−14.8
Sum, rounded to a whole point						−25

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	90,572	2429.3	− 2432	−2.7	× 26 / 62	−1.1
4	90,573	2428.9	− 2473	−44.1	× 17 / 62	−12.1
5	90,576	2511.8	− 2502	9.8	× 19 / 62	3
Sum, rounded to a whole point						−10

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,197	2424.9	− 2432	−7.1	× 21 / 75	−2
4	91,198	2448.5	− 2473	−24.5	× 22 / 75	−7.2
5	91,199	2466.2	− 2502	−35.8	× 17 / 75	−8.1
6	91,200	2546.9	− 2531	15.9	× 15 / 75	3.2
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	91,451	2453.5	− 2432	21.5	× 17 / 47	7.8
4	91,452	2500.6	− 2473	27.6	× 17 / 47	10
5	91,453	2580.1	− 2502	78.1	× 13 / 47	21.6
Sum, rounded to a whole point						39

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,339	2461.5	− 2432	29.5	× 24 / 64	11.1
4	91,340	2515.3	− 2473	42.3	× 12 / 64	7.9
5	91,341	2564.9	− 2502	62.9	× 16 / 64	15.7
6	91,342	2596.4	− 2531	65.4	× 12 / 64	12.3
Sum, rounded to a whole point						47

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	91,286	2508.6	− 2432	76.6	× 23 / 48	36.7
4	91,287	2488.3	− 2473	15.3	× 14 / 48	4.5
6	91,289	2558.1	− 2531	27.1	× 11 / 48	6.2
Sum, rounded to a whole point						47

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	90,990	2470.3	− 2432	38.3	× 21 / 51	15.8
4	90,991	2531.9	− 2473	58.9	× 17 / 51	19.6
5	90,992	2525.6	− 2502	23.6	× 13 / 51	6
Sum, rounded to a whole point						41

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. 17, −11, −25, −10, −14, 39, 47, 47, 41 → 14.6
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2015→2016: 28 · 2016→2017: 14 · 2017→2018: 15 · 2018→2019: 4 · 2019→2022: 53 · 2022→2023: 8 · 2023→2024: 0 · 2024→2025: 6 → average 16
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 16 × 2.66 = 42.6. Upper limit 57.2, lower limit −28.

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.