Carbonado Historical School 19

Carbonado, WA · Grades K–8

Seattle-Tacoma-Bellevue, WA

Neighborhood

Decoded Rank

All factors combined

Top 30% decoded

#104 of 680

Seattle-Tacoma-Bellevue, WA schools

★ Above Expected

#200 in WA

Achievement Rank

Raw test performance

Middle 40% achievement

#225 of 680

Seattle-Tacoma-Bellevue, WA schools

#295 in WA

places from achievement to Decoded Rank

Raw scores understate this school's performance; its decoded rank is substantially higher.

Data confidence:High218 students tested 8 years100% participation

Confidence is computed from sample size, year coverage, and participation rate. Higher confidence means the rank shift is stable across years and not driven by a single small cohort.

  • Tested students: total students with valid scores across all reported years.
  • Years of data: number of school years included. More years smooths year-to-year noise.
  • Participation: share of enrolled students who took the assessment. Low participation can bias scores.

What's driving this rank

Decoded Rank: #104 of 680

in Seattle-Tacoma-Bellevue, WA schools

Raw test scores rank this school #225, but after accounting for context, students here outperform what the data would predict. The Decoded Rank places it at #104.

Each component below is scored on a 0–100 within-metro scale. A qualitative band summarizes where the school lands.

  • About averagePerforms above what its context predictsCounts for 35% of the rank

    After accounting for income and demographics, does this school beat what the data would predict?

  • StrongStudents gain ground year over yearCounts for 30% of the rank

    Are kids at this school learning faster than typical for the metro?

  • StrongEquity within the schoolCounts for 15% of the rank

    Are students clustered at similar levels, or split between top and bottom?

  • About averageDirection over recent yearsCounts for 10% of the rank

    Is this school's Decoded Rank trending up or down across the years we have data for?

  • StrongMost students were testedCounts for 10% of the rank

    Was the rank computed against a representative share of the school's students?

Show the numbersFor the methodology-curious

Each component is converted to a 0–100 within-metro percentile (100 = top of the metro). "Contribution" is the percentile-points the component adds to (or subtracts from) the metro median before the schools are re-ranked into the composite.

Per-component contributions to this school's Decoded Rank composite. Weight is the share each component carries; percentile is the school's within-metro score on that component.
ComponentWeightPercentileContribution
Performs above what its context predicts 35%58+2.9
Students gain ground year over year 30%88+11.4
Equity within the school 15%81+4.7
Direction over recent years 10%50+0.0
Most students were tested 10%100+5.0

Note: this school's Alpha-only Decoded Rank is #285 (vs the composite #104). The composite includes cohort progression and other signals that diverge from the context-adjusted Alpha. See methodology.

How the Decoded Rank composite is computed

Why trust this?
  • Public data sources
  • Context-adjusted model
  • Confidence shown
  • Methodology published

This score uses state assessment data, NCES enrollment data, and Census ACS 5-year neighborhood data. The Decoded Rank adjusts for school context — student demographics, ELL/SPED service rates, and the socioeconomic profile of the surrounding tract — and shows how the school performs relative to expectation, not in absolute terms.

SchoolDecoder is one signal, not a verdict. Decoded Rank is a context-adjusted residual, not a causal claim about teaching quality. See full methodology →

All Rankings

How this school ranks across the metro, state, and among demographic peers.

ScopeAchievementDecodedShift
Seattle-Tacoma-Bellevue, WA (680 schools)#225#104
WA (1506 schools)#295#200
Among similar schools (6 peers)#2#2

Resource context

School inputs, not ranking points

These fields describe the school and surrounding neighborhood. They help readers interpret the page, but this is not a dollar-by-dollar or ratio-by-ratio scorecard and the fields here are not components of the Decoded Rank.

Enrollment
176
Free/reduced-price lunch
34.7%
Student-teacher ratio
14.7:1
Locale
Rural, fringe
School type
Regular public school
Enrollment model
Neighborhood attendance area
Neighborhood median income
$162,031ACS tract proxy
Neighborhood poverty
0.0%ACS tract proxy
SES index
78.8
Assessment data year
2025
CCD year
2024
ACS vintage
2020-2024

Within Carbonado School District: #1 of 1. View district

Performance Spread

How students are distributed across the four state-assessment proficiency levels — L1: below standard, L2: approaching, L3: meets (proficient), L4: exceeds. This describes the shape of results at the school, not their height.

Students at this school cluster closely on the proficiency ladder.

  • Level 1 — Below standard11%
  • Level 2 — Approaching standard27%
  • Level 3 — Meets standard (proficient)31%
  • Level 4 — Exceeds standard31%

Performance Spread measures how evenly students are distributed across the L1..L4 proficiency ladder, treating the levels as an ordered scale (L1=1, L2=2, L3=3, L4=4) and weighting each by its student share. A school where most students cluster at one level has a TIGHT spread; a school split between the bottom and top has a WIDE or BIMODAL spread. Bimodal fires only when BOTH tails are non-trivial AND the middle is relatively hollow (pct_L1 ≥ 15, pct_L4 ≥ 25, pct_L2 + pct_L3 ≤ 60). It describes shape — NOT how high the school's scores are. Methodology

Nearby Schools

Sorted by distance. Both rank columns shown so you can compare quickly.

SchoolAchievementDecodedShiftStoryConfidence
Wilkeson Elementary School#417#463Medium
White River Reengagement Program Rankings coming soon.
White River High School Rankings coming soon.
White River Early Learning Center Rankings coming soon.
Mountain Meadow Elementary#53#1High

Similar Schools

Schools with comparable demographics, income, and size. Both rank columns shown for direct comparison.

SchoolAchievementDecodedShiftStoryConfidence
Hayes Freedom High School Rankings coming soon.
Stevens Elementary School#251#617Medium
Camas Connect Academy Rankings coming soon.
10th Street School Rankings coming soon.
Coupeville Middle School#13#10Medium

Historical Ranks

Year-by-year decoded and achievement ranks. Pandemic-affected years are excluded — we don't interpolate scores across the gap.

YearAchievementDecodedShift
2025#225#104
2024#183#104
2023#224#123

Note: assessment transitions (where a state changes its test) are footnoted on the methodology page; trends are not computed across breakpoints.

Trajectory

2023: percentile 602024: percentile 662025: percentile 58

Holding steady

Based on 3 years (2023–2025).

Slope: -0.7 pct/yr (95% CI -54.3 to 53.0)

Low confidence

How this works: we fit a linear trend across the available years of Decoded percentile, then bucket the slope into a direction. Wide confidence intervals (uncertain trends) collapse to Holding steady. See the methodology page for thresholds.

Cohort Progression

Kids who started 3rd grade here in 2015 gained 32 proficiency points by 7th grade.

Based on 27 cohorts across math + ELA.

Learning rate: +7.2 proficiency points/yr (95% CI 1.3 to 13.0)

Medium confidence

Cohort 20152016201720182019202320242025 Slope
ELA · started 8th in 2015
G8
330
ELA · started 7th in 2015
G7
284
G8
278
-6.4
ELA · started 6th in 2015
G6
291
G7
291
G8
286
-2.8
ELA · started 5th in 2015
G5
275
G6
256
G7
291
G8
270
+1.9
ELA · started 4th in 2015
G4
330
G5
316
G6
282
G7
315
G8
-7.8
ELA · started 3rd in 2015
G3
263
G4
248
G5
294
G6
G7
+15.5
ELA · started 3rd in 2016
G3
G4
310
G5
338
G6
+28.6
ELA · started 3rd in 2017
G3
285
G4
314
G5
+29.3
ELA · started 3rd in 2018
G3
G4
300
G8
ELA · started 3rd in 2019
G3
315
G7
295
G8
290
-4.9
ELA · started 6th in 2023
G6
277
G7
291
G8
275
-1.1
ELA · started 5th in 2023
G5
254
G6
233
G7
233
-10.3
ELA · started 4th in 2023
G4
254
G5
300
G6
307
+26.5
ELA · started 3rd in 2023
G3
G4
281
G5
275
-6.3
ELA · started 3rd in 2024
G3
304
G4
275
-29.2
ELA · started 3rd in 2025
G3
Math · started 8th in 2015
G8
315
Math · started 7th in 2015
G7
268
G8
278
+9.4
Math · started 6th in 2015
G6
239
G7
254
G8
305
+32.8
Math · started 5th in 2015
G5
229
G6
276
G7
300
G8
300
+23.6
Math · started 4th in 2015
G4
305
G5
289
G6
312
G7
320
G8
319
+5.8
Math · started 3rd in 2015
G3
268
G4
262
G5
265
G6
263
G7
300
+6.4
Math · started 3rd in 2016
G3
G4
286
G5
295
G6
332
+23.1
Math · started 3rd in 2017
G3
275
G4
281
G5
285
+5.0
Math · started 3rd in 2018
G3
283
G4
278
G8
311
+6.2
Math · started 3rd in 2019
G3
G7
295
G8
310
+14.3
Math · started 6th in 2023
G6
277
G7
323
G8
308
+15.5
Math · started 5th in 2023
G5
208
G6
240
G7
247
+19.5
Math · started 4th in 2023
G4
300
G5
303
G6
303
+1.7
Math · started 3rd in 2023
G3
G4
300
G5
281
-18.8
Math · started 3rd in 2024
G3
263
G4
258
-4.2
Math · started 3rd in 2025
G3

How this works: we follow each grade-cohort across years through the school (3rd graders in 2023 are 4th graders in 2024, etc.) and fit a linear slope on a 100–400 proficiency-points scale built from the state assessment's four levels (L1=1, L2=2, L3=3, L4=4, weighted by student share). This is the same construction Stanford SEDA uses (edopportunity.org/methods); it's not student-level tracking — we measure the school's cohort, not individuals. See the methodology page for thresholds.

Evidence & technical detailClick to expand

School Alpha

School Alpha is the residual between actual and expected performance once school context is held constant. It is a context-adjusted estimate, not a causal claim about teaching quality.

Shrunk Alpha (95% CI)
+0.11 (95% CI: +0.01 to +0.20)

SES index components

SES method
Blended SES index (ACS + FRL)
SES index value
78.8
FRL %
34.7%
ELL %
SPED %
Tract median income (ACS 5-year)
$162,031
Tract poverty rate
0.0%
Tract % bachelor's+
28.9%

What "Decoded Rank" means

Decoded Rank converts School Alpha — the context-adjusted residual — into a parent-facing rank within the metro pool. A higher Decoded Rank than Achievement Rank means the school's raw scores understate its performance once neighborhood and school context are held constant. The reverse means raw scores overstate it. The rank is one signal, not a verdict.

Data & sources

Assessment data
2024–25 school year
NCES CCD vintage
2024
Census ACS 5-year vintage
2020-2024
Last updated
May 29, 2026
Methodology version
0.2.0

SchoolDecoder publishes context-adjusted residuals, not causal estimates. Decoded Rank is one signal — not a verdict on teaching quality. Read about limitations →