eduKate Sengkang Article Register | SK-01 to SK-20

First-wave article register

This register turns the 20-route estate map into article jobs. Each ID belongs to one route and one reader job. Existing strong URLs should be upgraded in place; a new URL is created only where no suitable owner already exists. Statuses used here are OPEN, ACTIVE, EXISTING OWNER, PROTECT and COMPLETE.

SK-01 — Commercial and Sengkang routing

SK-02 — Primary 1–3 English

• SK-02-010 — Primary 1 English Tuition Sengkang | Reading, Vocabulary & Writing Foundations — PUBLISHED / EXISTING SERVICE OWNER · WP14120 · publication verified 29 September 2026; replaces the ambiguous ACTIVE label, not the protected adjacent learning-stage pages.
• SK-02-020 — Primary 2 English Tuition Sengkang | Build Independent Reading & Writing — PUBLISHED / EXISTING SERVICE OWNER · WP14113 · publication verified 29 September 2026; existing stage and specialist owners remain protected.
• SK-02-030 — Primary 3 English Tuition Sengkang | Comprehension, Grammar & Composition — PUBLISHED / EXISTING SERVICE OWNER · WP14112 · publication verified 29 September 2026; not an unwritten article.
• SK-02-040 — Primary 1–3 English Syllabus and Progression — PUBLISHED / EXISTING MAIN ROUTE → nested foundations owner WP26478. WP33477 remains a PUBLISHED SUPPLEMENTARY HANDOFF, as its live closing route states; historical publication receipt: 10,001 substantive words. Do not recreate either URL or promote the supplementary page over the main route.
• SK-02-050 — Primary 1–3 Grammar Foundations — PUBLISHED / EXISTING MAIN ROUTE → nested foundations owner WP26482. WP33483 remains a PUBLISHED SUPPLEMENTARY HANDOFF; historical publication receipt: 10,005 substantive words.
• SK-02-060 — Primary 1–3 Vocabulary and Spelling — PUBLISHED / EXISTING MAIN ROUTE → nested foundations owner WP26519. WP33493 remains a PUBLISHED SUPPLEMENTARY HANDOFF; historical publication receipt: 10,008 substantive words.
• SK-02-070 — Primary 1–3 Reading Comprehension Foundations — PUBLISHED / EXISTING MAIN ROUTE → nested foundations owner WP26558. WP33500 remains a PUBLISHED SUPPLEMENTARY HANDOFF; historical publication receipt: 10,006 substantive words.
• SK-02-080 — Primary 1–3 Writing and Sentence Construction — PUBLISHED / EXISTING MAIN ROUTE → nested Writing Foundations owner WP26681. WP33511 remains a PUBLISHED SUPPLEMENTARY HANDOFF; historical publication receipt: 10,009 substantive words.
• SK-02-090 — Primary 1–3 Oral, Reading Fluency and Sound-to-Text Control — PUBLISHED / SUPPORTING CROSS-MODE BRIDGE · WP33519 · historical publication receipt: 10,000 substantive words. Preserve Listening and Oral Communication Foundations WP26831 as the adjacent foundations owner. The cross-mode bridge must not silently replace that broader job; detailed boundary review remains separate from publication verification.

SK-03 — Primary 4–6 English and PSLE English

• SK-03-010 — Primary 4 English Learning Guide: The Upper-Primary Transition From Understanding to Evidence — EXISTING OWNER WP 10872 / BATCH 01
• SK-03-020 — Primary 5 English Learning Guide: Building the PSLE Language System Before the Examination Year — EXISTING OWNER WP 10863 / BATCH 01
• SK-03-030 — Primary 6 English Learning Guide: Turning English Knowledge Into Reliable PSLE Performance — EXISTING OWNER WP 10855 / BATCH 01
• SK-03-040 — PSLE English Complete Guide: From Language Capability to Examination Craft — EXISTING OWNER WP 13828 / BATCH 01
• SK-03-050 — Primary 4 English Learning Guide | From Literal Detail to Supported Inference — PUBLISHED OWNER · WP34935 · 20,517 live-readback words.
• SK-03-060 — Primary 4 English Learning Guide | Reading-to-Writing Transfer: How Texts Build Better Comprehension and Composition — PUBLISHED OWNER · WP34940 · 20,534 live-readback words.
• SK-03-070 — Primary 5 English Learning Guide | The PSLE Runway: What Must Become Independent Before Primary 6 — PUBLISHED OWNER · WP34945 · 20,530 live-readback words.
• Protected adjacent PSLE owner — WP 11572: PSLE English Tuition Sengkang | What to Repair Before More Papers — retain as the specialist diagnosis-and-repair owner; do not overwrite with the broad PSLE apex job.
• Floor A — Primary 4 English: reading comprehension, evidence and inference; vocabulary and context; grammar and sentence control; narrative and informational reading; composition; situational writing; oral and listening; editing, study and progression — EXPAND TO DISTINCT READER JOBS AFTER COLLISION CHECK
• Floor B — Primary 5 English: PSLE runway; comprehension and synthesis; vocabulary precision; grammar and editing; composition and functional writing; visual and multimodal texts; oral and listening; independent study and diagnostic progression — EXPAND TO DISTINCT READER JOBS AFTER COLLISION CHECK
• Floor C — Primary 6 English: examination conversion; comprehension precision; grammar and vocabulary under pressure; writing decisions; oral and listening; timing, transfer, error analysis, revision and PSLE readiness — EXPAND TO DISTINCT READER JOBS AFTER COLLISION CHECK
• Floor D — PSLE English: Paper 1–4 and component guides; continuous writing; situational writing; visual text; grammar, vocabulary, editing, synthesis/cloze and comprehension; oral and listening; past papers, timing, diagnosis, mark conversion and final revision — EXPAND TO DISTINCT READER JOBS AFTER COLLISION CHECK
• SK-03 capacity target — approximately 150 distinct reader jobs across the four floors. This is a planning capacity, not a quota for new URLs. Existing strong owners are reused; new pages are admitted only for genuinely missing jobs.
• Longform standard — any substantially rebuilt or newly commissioned SK-03 owner targets 20,000+ substantive words, excluding navigation, headings, boilerplate and padding. Strong existing material is retained and built around rather than discarded merely to meet length.
• Estate controls — preserve established URLs and search ownership; check collisions before creation; route misplaced P4–P6/PSLE material to the correct learning architecture where warranted; no homepage, menu, theme or general-design changes.
• Production sequence — work in batches of four: inventory and claim owner → define scientific/reader job → research and estate synthesis → write or protect → format for rapid navigation → connect Spider/Web/Hidden/Deep routes → verify before the next batch.
• SK-03-080 — Primary 5 English Learning Guide | Comprehension Synthesis: Connect Evidence Across Sentences and Paragraphs — PUBLISHED OWNER · WP34959 · 20,606 live-readback words.
• SK-03-090 — Primary 5 English Learning Guide | From Feedback to Independent Revision: Edit Meaning Before Surface Errors — PUBLISHED OWNER · WP34961 · 20,551 live-readback words.
• SK-03-100 — Primary 5 English Learning Guide | Oral and Listening Response Control: Listen, Organise, Answer and Extend — PUBLISHED OWNER · WP34965 · 20,559 live-readback words.
• SK-03-110 — Primary 5 English Learning Guide | Multimodal Evidence: Read Words, Images, Captions and Layout as One Text — PUBLISHED OWNER · WP34968 · 20,557 live-readback words.
• SK-03-120 — Primary 6 English Learning Guide | Full-Paper Diagnosis: Turn One PSLE English Paper Into a Repair Map Before Doing Another — PUBLISHED OWNER · WP35200 · 20,526 live-readback words.
• SK-03-130 — Primary 6 English Learning Guide | Writing Under Time: Plan, Draft, Revise and Recover Without Losing Task Control — PUBLISHED OWNER · WP35203 · 20,543 live-readback words.
• SK-03-140 — Primary 6 English Learning Guide | Cross-Component Error Patterns: Find the Weak Link Behind Reading, Writing, Oral and Listening Losses — PUBLISHED OWNER · WP35208 · 20,507 live-readback words.
• SK-03-150 — Primary 6 English Learning Guide | Transfer After Correction: Prove a Repair on Fresh Work Before Returning to Full Papers — PUBLISHED OWNER · WP35211 · 20,523 live-readback words.

SK-04 — Secondary 1–2 English

• SK-04-010 — Secondary 1 English: Transition From Primary Answers to Secondary Reasoning — PUBLISHED OWNER · WP33529 · 10,004 substantive words at publication gate
• SK-04-020 — Secondary 2 English: Reading, Writing and Language Development — PUBLISHED OWNER · WP33539 · 10,028 substantive words at publication gate
• SK-04-030 — Secondary 1–2 Comprehension: Evidence and Inference — PUBLISHED OWNER · WP33596 · 10,008 substantive words at publication gate
• SK-04-040 — Secondary 1–2 Writing: Ideas, Organisation, Voice and Accuracy — PUBLISHED OWNER · WP33615 · 10,005 substantive words at publication gate

SK-05 — Secondary 3–4 English and SEC English

• SK-05-010 — Secondary 3 English: Building SEC-Ready Reading and Writing — PUBLISHED OWNER · WP33637 · 10,011 substantive words at publication gate
• SK-05-020 — Secondary 4 English: Examination-Year Control and Transfer — PUBLISHED OWNER · WP33657 · 10,008 substantive words at publication gate
• SK-05-030 — SEC English: What G1, G2 and G3 Students Need to Be Able to Do — PUBLISHED OWNER · WP33678 · 10,000 substantive words at publication gate
• SK-05-040 — Secondary English Examination Performance: Diagnose Before Drilling — PUBLISHED OWNER · WP33693 · 10,001 substantive words at publication gate

SK-06 — English skills and vocabulary

• SK-06-010 — How Vocabulary Works Across Reading and Writing — PROTECT · existing owner WP17747
• SK-06-020 — How Context Clues Work — PROTECT / HANDOFF → How Context Clues Build Vocabulary Independence · existing owner WP15663 · no duplicate article created
• SK-06-030 — How Grammar Supports Meaning Rather Than Rule Memorisation — PUBLISHED OWNER · WP33718 · 10,007 substantive words at publication gate
• SK-06-040 — How Multimodal Reading Works Across Words, Images, Captions and Layout — PUBLISHED OWNER · WP33785 · 10,018 substantive words at publication gate

SK-07 — Primary 1–3 Mathematics

• SK-07-010 — Primary 1 Mathematics: Number Sense, Representation and Early Problem Solving — PUBLISHED OWNER · WP33922 · 10,000 substantive words at publication gate
• SK-07-020 — Primary 2 Mathematics: Place Value, Operations and Model Building — PUBLISHED OWNER · WP33976 · 10,005 substantive words at publication gate
• SK-07-030 — Primary 3 Mathematics: Multiplication, Division, Fractions and Word Problems — PUBLISHED OWNER · WP34012 · 10,002 substantive words at publication gate
• SK-07-040 — Primary 1–3 Mathematics Tuition: How Foundations Compound — PUBLISHED OWNER · WP34025 · 10,002 substantive words at publication gate

SK-08 — Primary 4–6 Mathematics and PSLE Mathematics

• SK-08-010 — Primary 4 Mathematics: Fractions, Decimals, Measurement and Multi-Step Problems — PUBLISHED OWNER · WP34045 · 11,721 substantive words at publication gate
• SK-08-020 — Primary 5 Mathematics: Ratios, Percentages, Volume and Problem Representation — PUBLISHED OWNER · WP34077 · 10,033 substantive words at publication gate
• SK-08-030 — Primary 6 Mathematics: PSLE Readiness and Transfer — PUBLISHED OWNER · WP34108 · 10,000 substantive words at publication gate
• SK-08-040 — PSLE Mathematics: Diagnose Topic, Representation, Procedure and Decision Errors — PUBLISHED OWNER · WP34162 · 10,059 substantive words at publication gate

SK-09 — Secondary 1–2 Mathematics

• SK-09-010 — Secondary 1 Mathematics: G1, G2 and G3 Transition Guide — PROTECT / HANDOFF → Secondary 1 Mathematics Tuition Sengkang | The Primary-to-Secondary Math Reset · canonical year owner WP11121; G1/G2/G3 supporting route retained at existing Advanced Mathematics Tutorials owner
• SK-09-020 — Secondary 2 Mathematics: Algebra, Geometry, Ratio and Data Reasoning — PROTECT / HANDOFF → Secondary 2 Mathematics Tuition Sengkang | Build the Bridge to Upper Secondary Math · canonical year owner WP11135
• SK-09-030 — Secondary 1–2 Mathematics: Why Representation Errors Become Algebra Errors — PUBLISHED OWNER · WP34388 · 10,010 substantive words at publication gate
• SK-09-040 — How to Build Secondary Mathematics Working That Can Be Checked — PROTECT / HANDOFF → How to Show Working in Secondary Mathematics — Protect Method Marks Without Writing Too Much · existing explicit working-and-method-marks owner WP32327

SK-10 — Secondary 3–4 Mathematics and SEC Mathematics

• SK-10-010 — Secondary 3 Mathematics: Functions, Geometry, Data and Multi-Step Reasoning — PROTECT / HANDOFF → Secondary 3 Mathematics Tuition Sengkang | Upper Secondary Math, Transfer & SEC Readiness · canonical year owner WP11148
• SK-10-020 — Secondary 4 Mathematics: SEC Examination Readiness — PROTECT / HANDOFF → Secondary 4 Mathematics Tuition Sengkang | SEC 2027+ Exam Preparation · canonical year owner WP11336
• SK-10-030 — SEC Mathematics G1, G2 and G3: What Changes and What Remains — PROTECT / HANDOFF → G1, G2 and G3 Mathematics Explained for Secondary School Parents · existing cross-level owner WP30479; related Full SBB and subject-level specialists remain protected
• SK-10-040 — Mathematics Paper 2: Model, Solve, Verify and Communicate — PROTECT / LEVEL-SPECIFIC HANDOFF → G2 Mathematics Paper 2: Modelling, Real-World Problems and Smart Question Choice · WP34196; G3 Mathematics Full-Paper Integration: Paper 1, Paper 2, Modelling, Stamina and Checking · WP34375. No generic cross-level Paper 2 duplicate created.

SK-11 — Additional Mathematics

• SK-11-010 — Additional Mathematics Tuition Sengkang | S3–S4 Learning System — EXISTING OWNER · WP11345
• SK-11-020 — Additional Mathematics Study Guide | SEC G2 & G3, Topics and Worked Examples — PROTECT · WP26293
• SK-11-030 — Why Students Struggle With Additional Mathematics Even When E-Math Is Strong — PUBLISHED OWNER · WP34458 · 10,002 substantive words at publication gate
• SK-11-040 — Additional Mathematics Functions and Algebra: The Invariant Structure — PROTECT / SPECIALIST HANDOFF → Functions, Transformations, Inverse Structure and Graph Reasoning + Symmetry, Invariants and Reversible Transformations. No competing broad duplicate created.
• SK-11-050 — Additional Mathematics Examination Training: Selection, Working and Verification — PROTECT / SPECIALIST HANDOFF → Method Economy, Shortest Safe Routes and Mark Efficiency + Verification, Timing and Examination Recovery + A-Math Mock Exams. No duplicate examination-training owner created.

SK-12 — Primary 3–4 Science

• SK-12-010 — Primary 3 Science: Observation, Classification and Life Cycles — PROTECT / HANDOFF → Primary 3 Science Tuition Sengkang | Observe, Classify & Explain · canonical year owner WP10646; life-cycle and topic specialists remain protected children.
• SK-12-020 — Primary 4 Science: Systems, Matter, Heat and Evidence — PROTECT / HANDOFF → Primary 4 Science Tuition Sengkang | Relationships, Evidence & Explanation · canonical year owner WP10651; systems, matter, heat and evidence specialists remain protected children.
• SK-12-030 — Observation, Inference and Conclusion in Primary Science — PROTECT → Observation vs Inference vs Conclusion | Science Learning Guide · existing process owner WP15497; year-specific P4/P5/P6 process pages remain protected.
• SK-12-040 — How Fair Tests Work: Variables, Controls and Valid Conclusions — PROTECT / HANDOFF → Primary 3 Science Tuition | Experiments, Fair Tests and Evidence for Beginners · existing foundational fair-test owner WP30095; advanced investigation-design specialists remain protected.

SK-13 — Primary 5–6 Science and PSLE Science

• SK-13-010 — Primary 5 Science: Variables, Systems and Experimental Design — PROTECT / HANDOFF → Primary 5 Science Tuition Sengkang | Systems, Variables & PSLE Foundations · canonical year owner WP10656; experimental-design specialists remain protected children.
• SK-13-020 — Primary 6 Science: Integration Across Systems, Energy and Interactions — PROTECT / HANDOFF → Primary 6 Science Tuition Sengkang | 2026 PSLE Science & Scientific Reasoning · canonical year owner WP11270; integrated multi-concept reasoning remains a protected specialist route.
• SK-13-030 — PSLE Science: State, Describe, Explain, Compare and Predict — PROTECT / HANDOFF → Science: Match the Command Word Before You Write the Science · live command-word owner WP34441; Primary 6 Science Open-Ended Answering Technique remains the broader PSLE response specialist.
• SK-13-040 — PSLE Science Retrieval Across Diversity, Cycles, Systems, Energy and Interactions — PROTECT → How to Build Retrieval Across Diversity, Cycles, Systems, Energy and Interactions for PSLE Science · exact existing owner WP21448.

SK-14 — Secondary Science

• SK-14-010 — How Scientific Models Help Students Explain What Cannot Be Seen Directly — PROTECT / HANDOFF → Scientific Models for Students: Physical, Conceptual, Mathematical and Computer Models · existing models owner WP30829.
• SK-14-020 — How Scientific Explanation Works: Claim, Evidence, Mechanism and Limits — PROTECT / HANDOFF → How to Write Scientific Explanations: Claim, Evidence, Reasoning and Mechanisms · existing explanation owner WP30992; evidence-boundary specialists remain protected.
• SK-14-030 — How Students Distinguish Variables, Controls and Confounders — PROTECT / HANDOFF → Fair Tests | Variables, Controls & Valid Conclusions · canonical fair-test owner WP15483 + Scientific Method: Investigation Decisions, Variables and Evidence · advanced investigation specialist.
• SK-14-040 — How Unexpected Results Reveal Hidden Variables — PROTECT → How Unexpected Results Reveal Hidden Variables in Science · exact existing owner WP15828.

SK-15 — Learning Castle and study methods

• SK-15-010 — How Learning Works | The eduKate Sengkang Mechanism Map — PROTECT · exact existing owner WP18122
• SK-15-020 — How Studying Works | From Study Activity to Durable Learning — PROTECT · exact existing owner WP22004
• SK-15-030 — How Retrieval Practice Works When Students Need Transfer — PROTECT / HANDOFF → How Retrieval Practice Works | Bringing Knowledge Back Without Looking · canonical retrieval owner WP17656; transfer-specific teaching support remains protected at the existing retrieval-practice teaching route.
• SK-15-040 — How Feedback Changes Learning When Students Actually Use It — PROTECT / HANDOFF → How Feedback Works in Learning | From Information to Better Independent Performance · canonical feedback owner WP17545; marked-paper and learning-from-mistakes routes remain protected children.

SK-16 — Examination performance

• SK-16-010 — Why Students Go Blank in an Exam Even After Studying — EXISTING OWNER · WP26281
• SK-16-020 — Why Tuition Practice Improves but School Exam Marks Do Not Transfer — EXISTING OWNER · WP26284
• SK-16-030 — Self-Marking Past Papers Without Inflating the Score — EXISTING OWNER · WP26266
• SK-16-040 — Changing Answers in Multiple-Choice Exams Without Guessing Again — EXISTING OWNER · WP26265
• SK-16-050 — How Examination Timing Is Diagnosed and Repaired — PROTECT / HANDOFF → How Examination Performance Works | When Learning Has to Survive Time, Pressure and Independence · broad performance owner WP17610; Examination Craft | When Learning Has to Perform and subject-specific timing / triage routes remain protected children.

SK-17 — Parents, tuition and teaching support

• SK-17-010 — How Parents Can Tell Whether Tuition Is Changing Learning — PROTECT / HANDOFF → First Four Weeks of Tuition | What Progress Should Look Like · exact progress-evidence owner WP26313 + How to Work With Your Child’s Tutor · broader parent-review owner WP32114
• SK-17-020 — When Tuition Is Necessary and When It Is Not — PROTECT → Does My Child Actually Need Tuition? · exact existing decision owner WP17486; When to Stop Tuition remains the release/exit specialist
• SK-17-030 — How Tutors Diagnose the First Weak Link — PROTECT / HANDOFF → How Learning Diagnosis Works | From Visible Difficulty to the First Useful Weak Link · canonical diagnosis owner WP17596 + How to Work as a Tutor · tutor-professional route WP34037
• SK-17-040 — When a Student Should Change Tutor, Method or Practice Structure — PROTECT / HANDOFF → The Tutor System | How Parents, Students and Tutors Work Together · broad continue/change/reduce owner WP31803 + How to Work With Your Child’s Tutor · parent decision route WP32114; subject-specific switching and method-conflict pages remain protected children

SK-18 — Algorithms, computing and advanced mathematics

• SK-18-010 — Bareiss Algorithm: Exact Determinants and Fraction-Free Elimination — PUBLISHED / PROTECT · existing owner WP19952 · publication checked 29 September 2026.
• SK-18-020 — Bostan–Mori: Fast Linear Recurrences Through Generating Functions — PUBLISHED / PROTECT · existing owner WP19525 · publication checked 29 September 2026.
• SK-18-030 — Booth’s Algorithm: Minimal String Rotation and Candidate Elimination — PUBLISHED / PROTECT · existing owner WP20088 · publication checked 29 September 2026.
• SK-18-040 — Amanatides–Woo: Robust Grid Traversal and Ray Marching — PUBLISHED / PROTECT · existing owner WP19838 · publication checked 29 September 2026.
• SK-18-050 — Hirschberg’s Algorithm: Linear-Space Sequence Alignment — PUBLISHED / PROTECT · existing owner WP19880 · publication checked 29 September 2026. This is not the separate Hirschberg–Sinclair leader-election algorithm.
• SK-18-060 — PAVA: Isotonic Regression and Monotone Fitting — PUBLISHED / PROTECT · existing owner WP19955 · publication checked 29 September 2026.

SK-19 — Advanced science and world science

• SK-19-010 — How Electrochemical Potential and the Nernst Equation Work — PUBLISHED OWNER · WP34671 · 10,200 substantive words at publication gate
• SK-19-020 — How Electron Transfer Theory Connects Thermodynamics and Kinetics — PROTECT / HANDOFF → How to Learn Marcus Electron Transfer Theory: From Redox Thermodynamics to Reorganisation Energy, Activation Barriers, Electronic Coupling and the Inverted Region · existing functional owner WP21299; transition-state and electrochemistry specialist routes remain protected
• SK-19-030 — How Molecular Measurement Techniques Turn Hidden Structure Into Evidence — PUBLISHED OWNER · WP34682 · 10,009 substantive words at publication gate
• SK-19-040 — How Biological Recycling Systems Reuse Molecular Components — PUBLISHED OWNER · WP34710 · 10,089 substantive words at publication gate

SK-20 — Estate archaeology and collision repair

• SK-20-010 — Primary Mathematics Tuition Cannibalisation Map — REPAIRED / MONITOR · canonical P3/P5/P6 year owners now explicitly receive handoffs from older broad Advanced Mathematics siblings; planning/dependency-diagnosis/topic-integration children were narrowed; six legacy Mathematics siblings received clearer SERP metadata. The GSC “best math tuition in Sengkang” cluster is already structurally repaired on WP11202 (parent comparison checklist) versus WP13829 (canonical Mathematics tuition/service owner); the finalized GSC window ends 25 Sep and predates those 26–27 Sep role repairs, so no extra homepage change was made.
• SK-20-020 — Duplicate Secondary English Locality Routes: Owner and Adjacent-Cloud Repair — REPAIRED / MONITOR · Secondary 1–4 local Sengkang tuition/service pages WP10663/WP10670/WP10726/WP10738 now explicitly route to learning-stage knowledge owners WP33529/WP33539/WP33637/WP33657, and those knowledge owners reciprocally route back to the local service pages; URLs and visible titles preserved.
• SK-20-030 — Punggol and Other Locality Leakage on eduKateSengkang — REPAIRED / MONITOR · four core legacy Punggol gateways retained in place and given explicit locality handoffs to eduKatePunggol: English WP13973, Secondary English WP11941, Primary Mathematics WP11832, Secondary Mathematics WP11842; no URL, visible-title, redirect or deletion change.
• SK-20-040 — Orphan and Weakly Connected High-Impression Pages — REPAIRED / MONITOR · Algorithms & Computing Hub WP21155 and Complete Algorithms & Computing Index WP21156 now directly route to Link–Cut Trees WP19581, Bostan–Mori WP19525, Treap Algorithms WP19188 and Kabsch–Umeyama WP19986.
• SK-20-050 — Search-Result CTR Repair for High-Ranking Knowledge Pages — REPAIRED / MONITOR · GSC-backed SEO-title/description repair applied to WP19581, WP19525, WP19188 and WP19986; visible titles, URLs and bodies preserved; measure only after recrawl and a new finalized GSC window.

SK-20 current consolidation candidates

These are overlap/collision findings from the live hubbing audit. All URLs remain published. No merge, redirect, retitle or deletion is authorised by this note.

Resolved during live audit — Primary 2 Mathematics

The earlier Primary 2 overlap is no longer treated as an active collision. One sibling has since been retargeted to Why Primary 2 Word Problems Go Wrong: From Keywords to Mathematical Relationships, while Primary 2 Mathematics: Multiplication, Division, Fractions and Word Problems retains the broad level-guide job. Status: RETARGETED / COLLISION REDUCED.

Primary 3 Mathematics overlap

• Primary 3 Mathematics: Fractions, Models, Multiplication and Multi-Step Problem Solving
• The Primary 3 Multi-Step Reasoning Shift: How Students Learn to Plan Before Calculating

The later sibling has been narrowed toward planning-before-calculating, but both still occupy adjacent multi-step reasoning territory. Status: COLLISION REDUCED / REVIEW BOUNDARY.

Primary 5 Mathematics overlap

• Primary 5 Mathematics: Ratio, Percentage, Fractions, Decimals and Multi-Step Problems
• Why Primary 5 Mathematics Marks Fall: Hidden Dependency Gaps Behind Fractions, Percentage and Ratio

The later sibling has been retargeted toward diagnosis of falling marks and dependency gaps, reducing but not eliminating overlap with the broad Primary 5 guide. Status: COLLISION REDUCED / REVIEW BOUNDARY.

Primary 6 Mathematics overlap

• Primary 6 Mathematics: PSLE Problem Solving, Revision and Exam Control
• Primary 6 Mathematics: PSLE Problem Solving, Ratio, Speed, Algebra and Exam Control

Both own PSLE problem solving, mixed-topic integration, revision and exam control. The second page adds explicit topic breadth but remains substantially adjacent. Status: CONSOLIDATION CANDIDATE.

Advanced Science Chemistry title collision

• Chemistry for Beginners: Matter, Particles, Mixtures and Chemical Changes
• Chemistry for Beginners: Matter, Particles, Mixtures and Chemical Changes

The two live URLs have the same public title and very similar beginner-Chemistry scope, but their saved bodies are not identical. Status: CANONICAL COLLISION / CONSOLIDATION CANDIDATE.

Advanced Science Scientific Method overlap

• Scientific Method for Students: Questions, Hypotheses, Variables, Fair Tests and Evidence
• Scientific Method for Students: Variables, Fair Tests, Data and Conclusions

Both are large student investigation systems covering variables, fair tests, measurement, data, evidence and conclusions. Their saved bodies differ, but their reader jobs substantially overlap. Status: CONSOLIDATION CANDIDATE.

Advanced Science Project Ideas overlap

• Science Project Ideas for Students: 80 Safe Investigations From Primary to Secondary
• Science Project Ideas: Safe Experiments, Fair Tests and Measurable Questions

Both provide large inventories of safe student investigations and extensive guidance on measurable questions, variables and fair-test design. The bodies are not identical but the search and reader jobs substantially overlap. Status: CONSOLIDATION CANDIDATE.

Preservation rule: keep all active candidates live until a separate canonical-owner review compares search ownership, links, content depth and reader intent. The hubbing pass records collisions and recognises later retargeting, but does not choose a winner.

SK-20 newest overlap findings

Advanced Science Exam Techniques cluster

• Science Exam Techniques: How to Answer MCQ, Open-Ended, Data and Experiment Questions
• Science Exam Techniques: MCQ, Open-Ended Questions, Data, Timing and Checking
• Science Exam Techniques: Past Papers, Command Words, Timing and Checking

All three are large examination-performance guides covering command words, question reading, MCQ/open-ended strategy, graphs/data, experiment questions, timing and checking. The third adds stronger past-paper framing, but the search and reader jobs substantially overlap. Status: CONSOLIDATION CANDIDATE / REQUIRE CANONICAL REVIEW.

Secondary 2 Mathematics boundary

• Secondary 2 Mathematics: Algebra, Ratio, Graphs and the Bridge to Upper Secondary
• Why Secondary 2 Mathematics Is the Bridge Year: Algebra, Graphs, Factorisation and Upper-Secondary Readiness

The first is a broad level guide across algebra, ratio, graphs, geometry, statistics, probability and study cycle. The second is more explicitly a dependency/readiness and upper-secondary bridge article. They remain adjacent but can be defended as separate reader jobs if that distinction stays visible. Status: REVIEW BOUNDARY / NOT YET A CONSOLIDATION CANDIDATE.

Preservation rule: no retitle, redirect, merge or deletion is performed by this audit note. Any consolidation requires a separate canonical-owner review using live search ownership, links and reader intent.

SK-20 Science News overlap

• How to Read Science News and Evaluate Scientific Claims, Evidence and Research
• How to Read Science News and Evaluate Scientific Claims

Both are large scientific-literacy guides spanning Primary-to-Secondary readers. Their heading maps substantially overlap across claim/evidence/source checks, primary vs secondary sources, study design, sampling and selection bias, control groups, blinding, correlation/causation and research-quality appraisal. The bodies are not identical, but the search and reader jobs are highly adjacent. Status: CONSOLIDATION CANDIDATE / REQUIRE CANONICAL REVIEW.

Preservation rule: keep both URLs live until a separate canonical-owner review compares search ownership, internal/external links, content depth and reader intent. No merge, redirect, retitle or deletion is authorised here.

SK-20 exact-title duplicate audit — 25 Sep 2026

These duplicate-title groups were found during the live estate hubbing audit. All URLs remain published and reachable. This note records the collision only; it does not choose a canonical winner, merge content, redirect or delete anything.

Advanced Science — Science notes

• How to Take Science Notes: Cornell Notes, Diagrams, Summaries and Retrieval
• second live URL with the same public title

Advanced Science — presentations and posters

• Science Presentations and Posters: How to Explain Projects, Data and Results Clearly
• second live URL with the same public title

Sengkang local — malls guide

• Every Mall in Sengkang Compared
• second live URL with the same public title

Sengkang local — LRT guide

• Sengkang LRT Guide 2026: East Loop, West Loop, Stations, Transfers and Current Works
• second live URL with the same public title

Preservation rule: keep both URLs live until a separate canonical-owner review compares search ownership, backlinks/internal links, content depth, freshness and reader intent.

SK-20 near-collision audit — local guides and Science

These pairs have different live URLs and non-identical bodies, but their heading maps and reader jobs overlap enough to require canonical review. No consolidation is performed here.

Sengkang HDB guides

• Rivervale, Compassvale, Anchorvale, Fernvale and What Buyers Compare
• Neighbourhoods, Flat Ages, Transport and What Buyers Should Compare

Both cover the four Sengkang neighbourhoods, transport, schools, amenities, housing choice and buyer comparison. Status: CONSOLIDATION CANDIDATE.

Primary Schools in Sengkang guides

• A Parent’s Local Guide 2026
• Locations, Neighbourhoods and School Routes

Both organise Sengkang primary schools by neighbourhood and explain distance, P1 registration, school comparison and parent choice. Status: CONSOLIDATION CANDIDATE.

Advanced Science — scientific diagrams

• Biology, Apparatus, Circuits, Particles and Forces
• Biology, Circuits, Apparatus, Rays and Forces

Both are large cross-stage diagram-convention guides covering biology, apparatus, circuits, labels, arrows, scale and representation rules. Status: CONSOLIDATION CANDIDATE.

Advanced Science — AI study safely

• Verify Answers, Sources and Your Own Learning
• Learn, Verify and Stay Independent

Both are large Primary-to-Secondary AI-for-Science protocols covering attempt-first use, hints, verification, privacy, academic integrity, hallucinations, source checking and independent learning. Status: CONSOLIDATION CANDIDATE.

Preservation rule: keep every URL live until a separate canonical-owner review compares search ownership, links, freshness, body depth and reader intent.

How the register grows

Later batches continue in reserved tens. New article jobs are admitted only when they have a distinct reader purpose, an existing or declared owner, and a return path. If a search need is already served by a strong page, the correct action is usually to protect, modernise or surgically improve that page rather than create another URL.