English + E-Math + A-Math + Science → plugs into O-Level OS (Almost-Code v1.1)

Publishing role: This hub turns “secondary subjects” into a repairable system.
It standardises: mastery definition, failure modes, sensors, repair loops, and gate proofs—so every subject page is executable and comparable.

Connect subject interests to school choices Compare schools and their recorded subjects, CCAs and programmes. Confirm current subject combinations and eligibility directly with each school. Open the secondary school directory.

0) Header Lock

			
SYSTEM: Education OS
HUB: Singapore Secondary Subject OS Directory
CITY/NATION: SGP-SIN / SGP
ZOOM LINK: Z5 (city) ↔ Z0 (student)
GATE PLUG-IN:
  - O-Level OS (Singapore)
  - (downstream) PSLE OS link (for foundation references)
REFERENCE: CivOS (P0–P3)
PRIMARY PURPOSE:
  Provide a standard executable directory for Sec 1–4 subjects:
    - mastery (P3)
    - top failure modes (GF*)
    - sensor pack (P-S* + subject sensors)
    - repair loops (GR*)
    - O-Level proofs (OL-S*)

		

1) Subject Set (Directory Index)

			
SEC 1–4 SUBJECT OS SET (SGP):
  - SGP Secondary English OS (Sec 1–4)
  - SGP Secondary E-Math OS (Sec 1–4)
  - SGP Secondary A-Math OS (Sec 3–4)  [Sec2→3 jump protected]
  - SGP Secondary Science OS (Sec 1–2)
  - SGP O-Level Physics OS (Sec 3–4)
  - SGP O-Level Chemistry OS (Sec 3–4)
  - SGP O-Level Biology OS (Sec 3–4)

		

(If you want a lighter first pass: English + E-Math + A-Math + Combined Science.)

2) Standard Subject Entry Schema (Copy-Paste Template)

			
SUBJECT_ENTRY_SCHEMA:
  SUBJECT_ID: <SGP-SEC-...> (stable)
  SUBJECT_NAME: <string>
  YEARS: <Sec1–Sec4 or Sec3–Sec4>
  VERIFICATION GATE:
    - O-Level OS (Singapore)
  P3 MASTERY:
    - (retrieval, transfer, timed reliability, recovery)
  TOP FAILURE MODES:
    - 8–12 modes mapped to GF*
  SENSOR PACK:
    - P-S1..P-S5
    - subject-specific sensors
    - O-Level proof sensors (OL-S*)
  REPAIR LOOPS:
    - GR1, GR2, GR3, GR4, GR6, GR8
    - plus GR5/GR11/GR12 when applicable
  FAILURE TRACE + REPAIR TRACE:
    - required schematic chain
  PORTS:
    - O-Level OS, PSLE OS, GF library, GR library

		

3) Shared Sensor Pack (Secondary Standard)

			
PHASE SENSORS (SECONDARY STANDARD):
  P-S1 retrieval reliability
  P-S2 error histogram (concept/execution/attention)
  P-S3 time-to-solve distribution
  P-S4 transfer under wrapper variation
  P-S5 timed stability variance

		

			
O-LEVEL PROOF SENSORS (SECONDARY STANDARD):
  OL-S1 Sec2→Sec3 jump risk (for A-Math + abstraction-heavy subjects)
  OL-S2 multi-subject stability index
  OL-S3 timed vs untimed gap
  OL-S4 transfer gap under novelty
  OL-S5 error-repeat density
  OL-S6 repair latency vs exam horizon
  OL-S7 tuition masking factor (dependency vs competence)
  OL-S8 burnout risk proxy

		

4) Shared Failure Cluster (Secondary Standard)

			
SECONDARY DOMINANT GF CLUSTER (SGP):
  GF1 language drift (worded questions)
  GF2 practice without model
  GF3 compression without buffers
  GF5 transition shock amplification (Sec2→3)
  GF6 timed execution collapse
  GF7 late repair trap
  GF8 tuition masking
  GF9 transfer failure under novelty
  GF12 burnout tail

		

5) Shared Repair Set (Secondary Standard)

			
SECONDARY DOMINANT GR SET (SGP):
  GR8 early-warning thresholds
  GR1 buffer build (concept spine)
  GR3 transfer audits (wrapper robustness)
  GR4 time-pressure loop (timed stability)
  GR2 error-log closure (repeat elimination)
  GR6 continuity loop (coordination stabiliser)
  GR11 pressure-safety scheduling (burnout control)
  GR12 algebra readiness stabilisation (Sec2→Sec3 protection)
  GR5 language-base loop (when GF1 present)
  GR7 masking control (proof-based independence)

		

6) Immediate Instantiations (so the hub is not empty)

6.1 SGP Secondary E-Math OS (Sec 1–4) — Mini Instance

			
SUBJECT_ID: SGP-SEC-EMATH
SUBJECT_NAME: Singapore Secondary E-Math OS
YEARS: Sec1–Sec4
VERIFICATION GATE: O-Level OS (Singapore)
P3 MASTERY:
  - retrieves methods without cues (P-S1)
  - transfers across worded/graphical/symbolic wrappers (P-S4)
  - executes under time with low volatility (P-S5)
  - sustains mixed-topic papers; recovers after mistakes
TOP FAILURE MODES:
  EM-F01 algebra base gaps (feeds Sec3 jump) (GF5 precursor)
  EM-F02 practice without model (GF2)
  EM-F03 word-problem wrapper collapse (GF1+GF9)
  EM-F04 timed collapse (GF6)
  EM-F05 topic partitioning (fails on mixed papers) (GF9)
  EM-F06 error-repeat density (no closure) (GF10 symptom)
  EM-F07 late repair trap (GF7)
  EM-F08 burnout tail (GF12)
SUBJECT SENSORS:
  EM-S1 algebra primitives integrity score
  EM-S2 method-selection accuracy on mixed sets
  EM-S3 worded-wrapper transfer score
  EM-S4 checking discipline rate
REPAIR LOOPS:
  {GR1, GR3, GR4, GR2, GR6, GR8} + {GR5 if worded drift} + {GR11 if overload}
PROOF (O-LEVEL READY hooks):
  - OL-S3 timed gap small
  - OL-S4 transfer holds across wrapper families
  - OL-S5 error-repeat density falling

		

6.2 SGP Secondary A-Math OS (Sec 3–4) — Mini Instance (Jump-Protected)

			
SUBJECT_ID: SGP-SEC-AMATH
SUBJECT_NAME: Singapore Secondary A-Math OS
YEARS: Sec3–Sec4
VERIFICATION GATE: O-Level OS (Singapore)
P3 MASTERY:
  - stable algebra manipulation + functions without cues
  - transfers across unfamiliar forms and mixed synthesis
  - executes under time with low volatility
  - recovers after chain breaks
TOP FAILURE MODES:
  AM-F01 Sec2→Sec3 algebra/abstraction jump collapse (GF5 signature)
  AM-F02 weak algebra primitives (GR12 required) (GF5 precursor)
  AM-F03 practice without model (GF2)
  AM-F04 transfer collapse on novel forms (GF9)
  AM-F05 timed execution collapse (GF6)
  AM-F06 chain-break instability (multi-step collapse) (AL-S1 analog)
  AM-F07 late repair trap (GF7)
  AM-F08 burnout tail (GF12)
SUBJECT SENSORS:
  AM-S1 algebra readiness index (maps to OL-S1)
  AM-S2 chain-break map (where steps fail)
  AM-S3 novelty transfer score (form variation)
  AM-S4 timed volatility (P-S5 focused)
REPAIR LOOPS:
  GR12 (signature) + GR8 + GR1 + GR3 + GR4 + GR2 + GR6 + (GR11 if overload)
PROOF (O-LEVEL READY hooks):
  - OL-S1 Sec3 jump risk low
  - OL-S3 timed gap small
  - OL-S4 transfer holds across novel forms
  - OL-S5 repeats collapse

		

6.3 SGP Secondary English OS (Sec 1–4) — Mini Instance

			
SUBJECT_ID: SGP-SEC-ENG
SUBJECT_NAME: Singapore Secondary English OS
YEARS: Sec1–Sec4
VERIFICATION GATE: O-Level OS (Singapore)
P3 MASTERY:
  - reads unseen texts accurately under time
  - answers by command-word compliance
  - writes coherent, structured responses with stable quality
  - transfers across genres/prompts without collapse
TOP FAILURE MODES:
  EN-F01 vocabulary/comprehension drift (GF1)
  EN-F02 writing structure instability under time (GF6)
  EN-F03 prompt-wrapper sensitivity (GF9)
  EN-F04 practice without model (templates only) (GF2→GF9)
  EN-F05 late repair trap (GF7)
  EN-F06 burnout tail (GF12)
SUBJECT SENSORS:
  EN-S1 command-word compliance rate
  EN-S2 comprehension accuracy under time
  EN-S3 output structure stability (paragraph logic)
  EN-S4 prompt transfer score
REPAIR LOOPS:
  GR5 + GR1 + GR3 + GR4 + GR2 + GR6 + GR8 + (GR11 if overload)
PROOF (O-LEVEL READY hooks):
  - OL-S3 timed gap reduced
  - OL-S4 transfer holds across unseen prompts
  - volatility low across papers

		

7) Ports (Internal Link Hooks)

			
PORTS (HUB):
  - O-Level OS (Singapore)  [primary gate]
  - PSLE OS (Singapore)     [foundation reference]
  - Singapore City Education OS (SGP-SIN)
  - Singapore Nation Education OS (SGP)
  - W4 GF Library
  - W5 GR Library
  - Comparatives:
      London↔Singapore (Z5)
      UK↔SGP (Z6)

		

Singapore Secondary Subject OS Directory (Sec 1–4) — Hub