{
  "_about": "Column reference for /data/school_year.{parquet,csv} \u2014 one row per school x year. ~55% of cells are STRUCTURALLY null: graduation is HS-only, acceleration MS-only, EML/SWD 2023+, star ratings 2022-2025, and 2026 is a partial year (MCAP + enrollment only, more sources land as MSDE publishes). A null means 'not published for that school/year', never zero. `years`/`applies_to` are computed from the built table.",
  "join_key": "school_code_str (+ year, spring-labelled)",
  "row_grain": "school x year",
  "excluded": "class size \u2014 the 2024 MCPS report redefined secondary class size (+~7 students district-wide), so a school x year series would invite false trends; query the warehouse domain='class_size' instead",
  "columns": {
    "school_code_str": {
      "description": "3-digit MCPS school code, zero-padded string \u2014 the join key for every other file in the bundle",
      "units": "code",
      "source": "schools"
    },
    "school_name": {
      "description": "Short school name",
      "units": "text",
      "source": "schools"
    },
    "school_type": {
      "description": "ES / MS / HS (a few special schools carry other codes)",
      "units": "enum",
      "source": "schools"
    },
    "cluster": {
      "description": "MCPS cluster(s) the school belongs to",
      "units": "text",
      "source": "schools"
    },
    "year": {
      "description": "School year, spring-year labelled (2026 = SY2025-26)",
      "units": "year",
      "source": "-"
    },
    "enrollment": {
      "description": "Official enrollment, all grades summed",
      "units": "students",
      "source": "enrollment",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SE",
        "SP",
        "SS"
      ]
    },
    "g8_enroll": {
      "description": "Grade-8 enrollment (the accel_pct denominator)",
      "units": "students",
      "source": "enrollment",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS",
        "SP",
        "SS"
      ]
    },
    "farms_pct": {
      "description": "Share of students eligible for free/reduced-price meals",
      "units": "%",
      "source": "mcps + msde",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ],
      "caveats": [
        "hybrid source: >=2023 from MCPS enrollment_subgroup; 2019-2022 from MSDE 'FARMS Pct'. MSDE top-codes FARMS at ~80% from FY2024 \u2014 never trend MSDE FARMS across 2023/2024"
      ]
    },
    "eml_pct": {
      "description": "Multilingual learner share of enrollment",
      "units": "%",
      "source": "mcps",
      "years": [
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ],
      "caveats": [
        "2023+ only (MCPS source)",
        "students exit the subgroup on becoming proficient \u2014 do not trend EML outcome measures over time"
      ]
    },
    "swd_pct": {
      "description": "Students with an IEP (special education) share",
      "units": "%",
      "source": "mcps",
      "years": [
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ],
      "caveats": [
        "2023+ only (MCPS source)"
      ]
    },
    "suspended_pct": {
      "description": "Unique students suspended out-of-school as % of enrollment (all students)",
      "units": "%",
      "source": "mcps",
      "years": [
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SE",
        "SP"
      ],
      "caveats": [
        "MCPS suppressed nearly every school from 2024 (9 real values in 2024, 7 in 2025) \u2014 recent years are null for most schools",
        "this is a RATE of unique students; warehouse domain='discipline_incidents' counts events \u2014 never mix the two"
      ]
    },
    "ela3_pct": {
      "description": "MCAP ELA grade 3 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "SP"
      ]
    },
    "ela4_pct": {
      "description": "MCAP ELA grade 4 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES"
      ]
    },
    "ela5_pct": {
      "description": "MCAP ELA grade 5 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "MS"
      ]
    },
    "ela6_pct": {
      "description": "MCAP ELA grade 6 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "MS",
        "SS"
      ]
    },
    "ela7_pct": {
      "description": "MCAP ELA grade 7 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS",
        "SS"
      ]
    },
    "ela8_pct": {
      "description": "MCAP ELA grade 8 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS",
        "SP"
      ]
    },
    "ela10_pct": {
      "description": "MCAP ELA grade 10 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "SP",
        "SS"
      ]
    },
    "ela_all_pct": {
      "description": "MCAP ELA proficiency, all grades pooled",
      "units": "%",
      "source": "assessments",
      "years": [
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ],
      "caveats": [
        "published 2021+ only"
      ]
    },
    "math3_pct": {
      "description": "MCAP math grade 3 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES"
      ]
    },
    "math4_pct": {
      "description": "MCAP math grade 4 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES"
      ]
    },
    "math5_pct": {
      "description": "MCAP math grade 5 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "MS"
      ]
    },
    "math6_pct": {
      "description": "MCAP math grade 6 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS",
        "SS"
      ]
    },
    "math7_pct": {
      "description": "MCAP math grade 7 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS",
        "SS"
      ],
      "caveats": [
        "excludes accelerated students taking a course assessment instead \u2014 a selected residual at grades 7-8, see MEASURES.md"
      ]
    },
    "math8_pct": {
      "description": "MCAP math grade 8 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS",
        "SP"
      ],
      "caveats": [
        "excludes accelerated students taking a course assessment instead \u2014 a selected residual at grades 7-8, see MEASURES.md"
      ]
    },
    "math_all_pct": {
      "description": "MCAP math proficiency, all grades pooled",
      "units": "%",
      "source": "assessments",
      "years": [
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SS"
      ],
      "caveats": [
        "published 2021+ only",
        "at HS this pools the Algebra-1 remainder \u2014 see MEASURES.md"
      ]
    },
    "science5_pct": {
      "description": "MCAP science grade 5 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "MS"
      ],
      "caveats": [
        "2023-2026 statewide science swings are assessment-level events, not instruction \u2014 see assessments_coverage.json"
      ]
    },
    "science8_pct": {
      "description": "MCAP science grade 8 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS",
        "SP"
      ],
      "caveats": [
        "2023-2026 statewide science swings are assessment-level events, not instruction \u2014 see assessments_coverage.json"
      ]
    },
    "science_hs_pct": {
      "description": "MCAP HS science (biology-linked) proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "HS",
        "SP"
      ],
      "caveats": [
        "2026 not yet published (MSDE partial release)"
      ]
    },
    "alg1_pct": {
      "description": "MCAP Algebra 1 proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS",
        "SP",
        "SS"
      ],
      "caveats": [
        "taken by accelerated middle schoolers AND by HS students who reach the course later \u2014 never quote a pooled rate; split by school_type"
      ]
    },
    "alg1_tested": {
      "description": "Algebra 1 tested count (bulk source only)",
      "units": "students",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "alg1_bound": {
      "description": "Suppression bound on the Algebra 1 row ('<=5%', '>=95%', 'suppressed') \u2014 bounded rows are informative, see QUERYING.md recipe 2",
      "units": "enum",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "geo_pct": {
      "description": "MCAP Geometry proficiency",
      "units": "%",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS"
      ],
      "caveats": [
        "sat almost entirely by accelerated middle schoolers \u2014 not an HS measure"
      ]
    },
    "geo_tested": {
      "description": "Geometry tested count (bulk source only)",
      "units": "students",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "HS",
        "MS"
      ]
    },
    "math8_tested": {
      "description": "Math 8 tested count; NULL where the Math-8 row is absent or suppressed",
      "units": "students",
      "source": "assessments",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS"
      ]
    },
    "accel_pct": {
      "description": "Share of grade 8 testing beyond Math 8 (in Algebra 1/Geometry instead): 100 * (1 - math8_tested / g8_enroll), clipped to [0, 100]",
      "units": "%",
      "source": "assessments + enrollment",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025,
        2026
      ],
      "applies_to": [
        "MS"
      ],
      "caveats": [
        "NULL where the Math-8 basis is absent or suppressed. The site's aggregate (budget-equity math pathway) counts those schools as zero testers instead \u2014 its district figures include them, this column does not",
        "assumes Math-8 testers are 8th graders; accelerated 7th graders in Math 8 push true shares slightly higher",
        "compare against farms_pct before ranking: r ~ -0.8"
      ]
    },
    "attendance_pct": {
      "description": "Attendance rate",
      "units": "%",
      "source": "climate",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "chronic_absent_pct": {
      "description": "Chronically absent share (missing >=10% of days)",
      "units": "%",
      "source": "climate",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "mobility_pct": {
      "description": "Student mobility rate (entrants + withdrawals)",
      "units": "%",
      "source": "climate",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP"
      ]
    },
    "ppe_total": {
      "description": "Per-pupil expenditure, total",
      "units": "$/student",
      "source": "finance",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SE",
        "SP",
        "SS"
      ],
      "caveats": [
        "always name the variant \u2014 federal share scales with poverty, so total vs state/local comparisons invert equity conclusions"
      ]
    },
    "ppe_state_local": {
      "description": "Per-pupil expenditure, state + local funds",
      "units": "$/student",
      "source": "finance",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SE",
        "SP",
        "SS"
      ]
    },
    "ppe_federal": {
      "description": "Per-pupil expenditure, federal funds",
      "units": "$/student",
      "source": "finance",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SE",
        "SP",
        "SS"
      ]
    },
    "star_rating": {
      "description": "MSDE accountability star rating (1-5)",
      "units": "stars",
      "source": "accountability",
      "years": [
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP"
      ],
      "caveats": [
        "published 2022-2025 only; methodology shifts across eras"
      ]
    },
    "acct_points_pct": {
      "description": "MSDE accountability total points earned",
      "units": "%",
      "source": "accountability",
      "years": [
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP"
      ]
    },
    "inexperienced_pct": {
      "description": "Teachers with < 3 years experience",
      "units": "%",
      "source": "educators",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "emergency_cred_pct": {
      "description": "Teachers on emergency/provisional credentials",
      "units": "%",
      "source": "educators",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "ES",
        "HS",
        "MS",
        "SP",
        "SS"
      ]
    },
    "grad_rate_4yr": {
      "description": "4-year adjusted-cohort graduation rate",
      "units": "%",
      "source": "graduation",
      "years": [
        2019,
        2021,
        2022,
        2023,
        2024,
        2025
      ],
      "applies_to": [
        "HS",
        "SP",
        "SS"
      ],
      "caveats": [
        "HS only"
      ]
    }
  }
}