• INTERACTIVE: Pattern Shapes - make make patterns, tessellations and pictures 
• INTERACTIVE: Geoboard - use virtual rubber bands to form shapes
• PRACTICE: Identify Planar and Solid Figures  (IXL)
• PRACTICE: Which Figure is Being Described?  (IXL)
• PRACTICE: Combining or Splitting 2-D Shapes (Study Ladder)
• PRACTICE: Attributes of 2-D Shapes (Study Ladder)
• PRACTICE: Grouping 2-D Shapes into their Attributes (Study Ladder)
• GAME: Shape Matching Game

• TEACHING VIDEOS: Classifying Two-Dimensional Figures  (Learn Zillion) - a collection of teaching videos teaching various parts of this standard

• TEACHING VIDEOS: Understand Categories and Subcategories of Two-Dimensional Figures  (Learn Zillion) - a collection of teaching videos teaching various parts of this standard

Classifying Triangles

• VIDEO: Classify Triangles Study Jams (Scholastic)
• VIDEO: Triangles (Math Antics)
• VIDEO: Triangles (Math is Fun)
• Clasifying Triangles Interactive and Descriptions (Math is Fun)
• SONG: Triangles Classification Song (A Parody of Lord's Royals Song)

• PRACTICE: Naming Types of Triangles (Study Ladder)
• PRACTICE: Types of Triangles (Math Games)
• PRACTICE: Types of Triangles (IXL)
• PRACTICE: Types of Triangles (Buzzmath)
• PRACTICE: Identify Triangles Quiz
• PRACTICE: Identification of Triangles Quiz
• GAME: Classifying Triangles Drag-and-Drop
• PRACTICE & GAME: Angles & Triangles 

• PRACTICE QUIZ: Classifying Triangles (easy)
• PRACTICE QUIZ: Classifying Triangles (challenge)
• PRACTICE QUIZ: Sum of Angles in a Triangle (challenge)
• PRACTICE QUIZ: Missing Angle in a Triangle (challenge)

Classifying Quadrilaterals 

• VIDEO: Classify Quadrilaterals Study Jams (Scholastic)
• VIDEO: Quadrilaterals (Math Antics)
• Quadrilaterals Interactive and Descriptions (Math is Fun)
• SONGS: Classifying Quadrilaterals (A Parody of Imagine Dragon's Radioactive Song)

• PRACTICE: Classify Quadrilaterals (Math Games)
• PRACTICE: Quadrilateral Shapes Game
• PRACTICE: Classify Quadrilaterals (IXL)
• INTERACTIVE: Classifying Quadrilaterals
• INTERACTIVE: Quadrilateral Quest - Do you Know Their Properties?
• INTERACTIVE: Quadrilateral Properties (Glencoe)
• GAME: Classifying Quadrilaterals
• GAME: Call of Geometry - Quadrilateral Warfare
• CHALLENGE: How Many Quadrilaterals Can You Make with the Eight-Dot Circle? Use this Interactive Geoboard (and choose the circle board) 

• PRACTICE QUIZ: Classifying Quadrilaterals (easy)  
• PRACTICE QUIZ: Classifying Quadrilaterals (challenge)
• PRACTICE QUIZ: Angles of Quadrilaterals (challenge)
• WORKSHEETS: Classify Shapes: Quadrilaterals (Common Core Sheets)