ALEX Classroom Resource

Students:

• Sort two-dimensional figures based on angle sizes or presence of parallel and/or perpendicular lines.

Example: Given a group of regular polygons, sort shapes into categories based on angle size as well as presence of parallel lines.
• Classify and name shapes using more than one characteristic.
• Identify a right triangle by labeling the right angle.

Students know:

• Two lines are parallel if they never intersect and are an equal distance apart.
• Two lines are perpendicular if they are at right angles to each other.
• A right triangle is a triangle that has one right angle.

Students are able to:

• Classify two-dimensional figures based on the presence or absence of parallel or perpendicular lines.
• Classify two-dimensional figures based on the presence or absence of angles of a specified size.
• Identify right triangles.

Students understand that:

• shapes are categorized based on attributes they possess in common such as angle size, side length, side relationships (parallel and perpendicular).

Learning Objectives:
M.4.28.1: Define right angle.
M.4.28.2: Recognize that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals).
M.4.28.3: Recognize rhombuses, rectangles, and squares as examples of quadrilaterals, and draw examples of quadrilaterals that do not belong to any of these subcategories.
M.4.28.4: Recognize and draw shapes having specified attributes such as a given number of angles or a given number of equal faces.
M.4.28.5: Identify triangles.

Students:
When given a variety of triangles,

• Measure sides and angles to classify triangles based on side length and angle measure.

Students know:

• Measurable attributes of triangles include length of side and angle measures.
• Appropriate tools and units of measure for length of side and angle measures.

Students are able to:

• Classify triangles according to side measures and angle measures.

Students understand that:

• triangles can be described and classified by their properties of side length, angle size, or cross-classify to include both side length and angle size.

Learning Objectives:
M.5.21.1: Define isosceles, equilateral, scalene, right and equiangular triangles; obtuse, acute, and right angle; vertex/vertices.
M.5.21.2: Identify a right triangle.
M.5.21.3: Sort and categorize shapes.
M.5.21.4: Recognize and draw shapes having specified attributes.

Students:
When given variety of two-dimensional figures,

• Use attributes of shapes to explain their classification in as many categories and subcategories as possible.
• Distinguish properties that are more general from those that are more specific and make connections between and within categories of figures.

Example: A quadrilateral is a figure with a general property of 4-sides, while a parallelogram is a specific type of quadrilateral with two pairs of opposite sides which are both parallel and congruent. Based on this hierarchy, all parallelograms are quadrilaterals, but not all quadrilaterals are parallelograms.

Students know:

• properties or attributes of two-dimensional shapes.

Students are able to:

• Classify quadrilaterals based on properties.

Students understand that:

• Quadrilaterals can be identified by general properties to more specific properties.
• Properties belonging to a category of two-dimensional figures also belong to all subcategories of that category.

Learning Objectives:
M.5.22.1: Define vertex/vertices and angle.
M.5.22.2: Identify that shapes in different categories (e.g., rhombuses, rectangles, and others) may share attributes (e.g., having four sides), and that the shared attributes can define a larger category (e.g., quadrilaterals).
M.5.22.3: Recognize and draw shapes having specified attributes such as a given number of angles or a given number of equal faces.
M.5.22.4: Identify triangles, quadrilaterals, pentagons, hexagons, heptagons, and octagons based on the number of sides, angles, and vertices.