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Geoboards

This lesson, one of a five-part unit from Illuminations titled “Investigating Shapes: Recognizing, Constructing, and Identifying Triangles,” students identify and recognize triangles using multiple representations, locate triangles in their... (Learn more)

Format: lesson plan (grade K–1 Mathematics)

Provided by: Illuminations

How do you build triangles?

In this lesson, the second in a four-part unit from Illuminations titled “Triangles,” students investigate basic properties of triangles. They then investigate the relationships among basic geometric shapes and communicate their findings to... (Learn more)

Format: lesson plan (grade K–1 Mathematics)

Provided by: Illuminations

How many triangles can you construct?

Students identify patterns in a geometrical figure (based on triangles) and build a foundation for the understanding of fractals. Illuminations provides activity sheets and detailed instructions for completing the lesson. Students will: ... (Learn more)

Format: lesson plan (grade 4–6 Mathematics)

Provided by: Illuminations

Investigating the concept of triangle and properties of polygons

This two-part example from Illuminations describes activities using interactive geoboards to help students identify simple geometric shapes, describe their properties, and develop spatial sense. This first part, Making Triangles, focuses attention on the... (Learn more)

Format: lesson plan (grade K–2 Mathematics)

Provided by: Illuminations

Making triangles

In this lesson, one of a four-part unit from Illuminations titled “Ladybug Adventures — Learning Geometry and Measurement Concepts,” students use 45- and 90-degree angles to create triangles and develop an understanding of the relationship... (Learn more)

Format: lesson plan (grade K Mathematics)

Provided by: Illuminations

Making virtual triangles

This lesson, one of a five-part unit from Illuminations titled “Investigating Shapes: Recognizing, Constructing, and Identifying Triangles,” students identify and recognize triangles using multiple representations interactive electronic geoboards... (Learn more)

Format: lesson plan (grade K Mathematics)

Provided by: Illuminations

Three sides

This lesson, one of a five-part unit from Illuminations titled “Investigating Shapes: Recognizing, Constructing, and Identifying Triangles,” students identify and recognize triangles using multiple representations. Students use attribute-blocks... (Learn more)

Format: lesson plan (grade K–1 Mathematics)

Provided by: Illuminations

Tracing and drawing

Students will continue to discuss attributes of triangles. They will trace and draw triangles individually, recognize objects in their environment that are shaped like triangles, and explain to the class how they recognized the shape. Students will:... (Learn more)

Format: lesson plan (grade K Mathematics)

Provided by: Illuminations

What can you build with triangles?

Students explore ways of building different basic shapes from triangles and investigate three dimensional shapes constructed from triangles. Illuminations provides an activity sheet and instructions for completing the lesson. Students use cut outs of two... (Learn more)

Format: lesson plan (grade 2 Mathematics)

Provided by: Illuminations

What's important about triangles?

Students explore the importance of the side lengths of a triangle and when triangles can or cannot be constructed on the basis of these lengths. Illuminations provides an activity sheet and detailed instructions for completing the lesson. Students... (Learn more)

Format: lesson plan (grade 4–5 Mathematics)

Provided by: Illuminations