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Classroom Resources
Notice and Wonder
The Year Game
Back to School Resources
Math Sightings
Video Lessons
Problems of the Week Resources
Reasoning & Sense Making Task Library
Student Explorations in Mathematics
Problems to Ponder
Illuminations
Figure This!
Activities with Rigor & Coherence - ARCs
Designing Innovative Lessons and Activities
Publications
Featured Books
Advertise
Mathematics Teacher: Learning and Teaching PK-12
Journal for Research in Mathematics Education
Mathematics Teacher Educator
Institutional Subscriptions
Rights and Permissions
Write, Review, Referee
Legacy Journals and Blogs
Standards & Positions
Principles to Actions
Position Statements
Catalyzing Change
Standards for Mathematics Teacher Preparation
Curriculum Focal Points
GAISE II
Focus in High School Mathematics
NCTM Standards
Advocacy
Policies and Recommendations
Advocacy Toolkit
Advocacy and Legislation
ESSER - District Solutions
Every Student Succeeds Act - ESSA Toolkit
NCTM Social Justice and Equity Resources
Capitol Hill Day 2023
Research
Research Briefs & Clips
Linking Research & Practice
Research Conference
Research Monographs
Journal for Research in Mathematics Education
Continuing the Journey
Conferences & Professional Development
NCTM Annual Meeting & Exposition
Professional Development Resources
Regional Conferences & Expositions
Research Conference
Virtual Conference
Interactive Institutes
Speaking at NCTM Events
Webinars
Professional Services
NCTM District Solutions
NCTM Teacher Education Program Review Training
NCTE-NCTM Joint Conference on Elementary Literacy & Mathematics
Exhibit, Advertise, Sponsor
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Delving Deeper: Extending a Classical Geometry Problem
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