Mark Twain Elementary School

Federal Way, WA · Grades ?–5

Seattle-Tacoma-Bellevue, WA

Neighborhood

Decoded Rank

All factors combined

Bottom 30% decoded

#516 of 678

plausibly #478–550

Seattle-Tacoma-Bellevue, WA schools

Below Expected

#1139 in WA

Achievement Rank

Raw test performance

Bottom 15% achievement

#646 of 678

Seattle-Tacoma-Bellevue, WA schools

#1410 in WA

places from achievement to Decoded Rank

Scores look modest, and students tend to slip relative to peers the longer they are enrolled.

Data confidence:High436 students tested 7 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: #516 of 678

in Seattle-Tacoma-Bellevue, WA schools

Raw test scores rank this school #646, but after accounting for context, students here outperform what the data would predict. The Decoded Rank places it at #516.

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

  • Below 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?

  • LowStudents 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%24-8.9
Students gain ground year over year 30%10-12.0
Equity within the school 15%86+5.4
Direction over recent years 10%50+0.0
Most students were tested 10%100+5.0

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 (678 schools)#646#516
WA (1503 schools)#1410#1139
Among similar schools (6 peers)#6#6

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
537
Free/reduced-price lunch
94.4%
Student-teacher ratio
16.8:1
Locale
Suburb, large
School type
Regular public school
Enrollment model
Neighborhood attendance area
Neighborhood median income
$78,189ACS tract proxy
Neighborhood poverty
0.2%ACS tract proxy
SES index
24.1
Assessment data year
2024
CCD year
2023
ACS vintage
2020-2024

Within Federal Way School District: #17 of 31.Middle quintile in district. 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 standard54%
  • Level 2 — Approaching standard26%
  • Level 3 — Meets standard (proficient)13%
  • Level 4 — Exceeds standard7%

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
Woodmont K-8 School#482#517High
Valhalla Elementary School#548#486High
Evergreen Middle School#668#625High
Star Lake Elementary School#479#341High
Thomas Jefferson High School Rankings coming soon.

Similar Schools

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

SchoolAchievementDecodedShiftStoryConfidence
Martin Luther King Jr Elementary#43#50High
Ridgeview Elementary#31#25High
Four Heroes Elementary#606#223High
Lakeview Hope Academy#634#275High
Mcclure Elementary School#18#24High

Historical Ranks

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

YearAchievementDecodedShift
2024#646#516
2023#655#567

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

Trajectory

2023: percentile 182024: percentile 24

Trending up

Based on 2 years (2023–2024).

Slope: +6.1 pct/yr (no CI — too few years)

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 2023 lost 18 proficiency points by 4th grade — declining, versus a metro median of about 0/yr.

Cohort-to-cohort variance is high — interpret the headline cautiously.

Learning rate: -6.5 proficiency points/yr (95% CI -17.8 to 4.8)

Low confidence

Cohort 2015201620172018201920232024 Slope
ELA · started 5th in 2015
G5
219
ELA · started 4th in 2015
G4
204
G5
253
+49.4
ELA · started 3rd in 2015
G3
223
G4
189
G5
206
-8.5
ELA · started 3rd in 2016
G3
215
G4
167
G5
204
-5.6
ELA · started 3rd in 2017
G3
170
G4
193
G5
213
+21.3
ELA · started 3rd in 2018
G3
210
G4
191
-19.1
ELA · started 3rd in 2019
G3
177
ELA · started 5th in 2023
G5
163
ELA · started 4th in 2023
G4
164
G5
186
+22.0
ELA · started 3rd in 2023
G3
205
G4
186
-18.3
ELA · started 3rd in 2024
G3
185
Math · started 5th in 2015
G5
208
Math · started 4th in 2015
G4
221
G5
222
+1.7
Math · started 3rd in 2015
G3
225
G4
213
G5
193
-15.9
Math · started 3rd in 2016
G3
262
G4
192
G5
186
-37.9
Math · started 3rd in 2017
G3
215
G4
176
G5
198
-8.9
Math · started 3rd in 2018
G3
222
G4
178
-43.3
Math · started 3rd in 2019
G3
189
Math · started 5th in 2023
G5
137
Math · started 4th in 2023
G4
165
G5
147
-17.6
Math · started 3rd in 2023
G3
180
G4
172
-7.6
Math · started 3rd in 2024
G3
170

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)
-0.32 (95% CI: -0.35 to -0.29)

SES index components

SES method
Blended SES index (ACS + FRL)
SES index value
24.1
FRL %
94.4%
ELL %
48.6% · WA OSPI Report Card Enrollment
SPED %
11.0% · WA OSPI Report Card Enrollment
Tract median income (ACS 5-year)
$78,189
Tract poverty rate
0.2%
Tract % bachelor's+
26.6%

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
2023–24 school year
NCES CCD vintage
2023
Census ACS 5-year vintage
2020-2024
Last updated
July 26, 2026
Methodology version
0.9.0
Source files (3)

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