Mojave River Academy - Silver Mountain: 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.

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	64,314	2343.5	− 2436	−92.5	× 11 / 257	−4
4	64,315	2368.3	− 2485	−116.7	× 11 / 257	−5
5	64,316	2379.9	− 2528	−148.1	× 21 / 257	−12.1
6	64,317	2399.9	− 2552	−152.1	× 33 / 257	−19.5
7	64,318	2433.0	− 2567	−134	× 47 / 257	−24.5
8	64,319	2414.5	− 2586	−171.5	× 52 / 257	−34.7
11	64,320	2447.1	− 2628	−180.9	× 82 / 257	−57.7
Sum, rounded to a whole point						−158

2022 from sb_ca2022_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	64,387	2315.9	− 2436	−120.1	× 14 / 248	−6.8
4	64,388	2346.8	− 2485	−138.2	× 19 / 248	−10.6
5	64,389	2372.9	− 2528	−155.1	× 20 / 248	−12.5
6	64,390	2401.0	− 2552	−151	× 36 / 248	−21.9
7	64,391	2418.1	− 2567	−148.9	× 42 / 248	−25.2
8	64,392	2419.5	− 2586	−166.5	× 51 / 248	−34.2
11	64,393	2450.2	− 2628	−177.8	× 66 / 248	−47.3
Sum, rounded to a whole point						−159

2023 from sb_ca2023_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
4	64,371	2356.9	− 2485	−128.1	× 15 / 290	−6.6
5	64,372	2368.8	− 2528	−159.2	× 24 / 290	−13.2
6	64,373	2392.5	− 2552	−159.5	× 24 / 290	−13.2
7	64,374	2408.0	− 2567	−159	× 50 / 290	−27.4
8	64,375	2396.1	− 2586	−189.9	× 47 / 290	−30.8
11	64,376	2431.7	− 2628	−196.3	× 130 / 290	−88
Sum, rounded to a whole point						−179

2024 from sb_ca2024_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	64,344	2298.6	− 2436	−137.4	× 16 / 315	−7
4	64,345	2341.2	− 2485	−143.8	× 13 / 315	−5.9
5	64,346	2386.9	− 2528	−141.1	× 19 / 315	−8.5
6	64,347	2368.1	− 2552	−183.9	× 42 / 315	−24.5
7	64,348	2404.6	− 2567	−162.4	× 41 / 315	−21.1
8	64,349	2404.5	− 2586	−181.5	× 62 / 315	−35.7
11	64,350	2433.2	− 2628	−194.8	× 122 / 315	−75.4
Sum, rounded to a whole point						−178

2025 from sb_ca2025_1_csv_v1.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	64,108	2293.0	− 2436	−143	× 18 / 368	−7
4	64,109	2349.6	− 2485	−135.4	× 27 / 368	−9.9
5	64,110	2384.8	− 2528	−143.2	× 36 / 368	−14
6	64,111	2392.0	− 2552	−160	× 51 / 368	−22.2
7	64,112	2396.9	− 2567	−170.1	× 55 / 368	−25.4
8	64,113	2394.3	− 2586	−191.7	× 49 / 368	−25.5
11	64,114	2428.3	− 2628	−199.7	× 132 / 368	−71.6
Sum, rounded to a whole point						−176

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −158, −159, −179, −178, −176 → −170
Typical year-to-year change: how far the result moved from each year to the next, ignoring up or down. 2019→2022: 1 · 2022→2023: 20 · 2023→2024: 1 · 2024→2025: 2 → average 6
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 6 × 2.66 = 16. Upper limit −154, lower limit −186.

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 2018–19, 2020–21, 2021–22, 2022–23, 2023–24, 2024–25, 2025–26.