Gladstone Street Elementary: 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.

Measured against the grade bars

The state's English test uses one scale for every grade, so a score means the same thing in grade 3 as in grade 5.

3rd The average 3rd grader scores 60 points under the grade 3 bar. 2372 vs. 2432.
4th The average 4th grader scores 32 points under the grade 3 bar. 2401 vs. 2432. The 4th-grade bar is 2473.
5th The average 5th grader scores 41 points under the grade 4 bar. 2433 vs. 2473. The 5th-grade bar is 2502.

2019 results. The English test covers reading, writing, listening and research together. "Meets standard" is the state's mark for being on track for that grade.

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	20,940	2372.6	− 2432	−59.4	× 58 / 171	−20.1
4	20,941	2395.1	− 2473	−77.9	× 49 / 171	−22.3
5	20,944	2468.7	− 2502	−33.3	× 64 / 171	−12.5
Sum, rounded to a whole point						−55

2016 from sb_ca2016_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	19,883	2383.6	− 2432	−48.4	× 43 / 159	−13.1
4	19,884	2405.6	− 2473	−67.4	× 64 / 159	−27.1
5	19,887	2452.1	− 2502	−49.9	× 52 / 159	−16.3
Sum, rounded to a whole point						−57

2017 from sb_ca2017_1_csv_v2.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	20,194	2383.2	− 2432	−48.8	× 59 / 172	−16.7
4	20,196	2402.3	− 2473	−70.7	× 51 / 172	−21
5	20,199	2449.1	− 2502	−52.9	× 62 / 172	−19.1
Sum, rounded to a whole point						−57

2018 from sb_ca2018_1_csv_v3.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	20,195	2372.6	− 2432	−59.4	× 48 / 162	−17.6
4	20,197	2408.8	− 2473	−64.2	× 64 / 162	−25.4
5	20,199	2451.3	− 2502	−50.7	× 50 / 162	−15.6
Sum, rounded to a whole point						−59

2019 from sb_ca2019_1_csv_v4.zip

Grade	Line in file	Average score	Standard Met	Distance	Students	Weighted
3	20,369	2372.3	− 2432	−59.7	× 50 / 168	−17.8
4	20,370	2400.5	− 2473	−72.5	× 51 / 168	−22
5	20,371	2432.5	− 2502	−69.5	× 67 / 168	−27.7
Sum, rounded to a whole point						−67

Step 2 · The average and the normal range

Average: add the yearly results and divide by how many there are. −55, −57, −57, −59, −67 → −59
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: 0 · 2017→2018: 2 · 2018→2019: 8 → average 3
Normal range: multiply the typical change by 2.66, then add it to the average and subtract it. 3 × 2.66 = 8. Upper limit −51, lower limit −67.

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".

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.