math · Grade 4
Geometry: Measuring and Classifying Angles
Read protractors and classify acute, right, and obtuse angles with structured practice.
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Explore the related learning targets, foundations and possible next connections.
Learning goals
- Read a protractor from its zero-degree baseline
- Classify acute, right, and obtuse angles
Before you begin
Identify an angle's vertex and rays and place a ray on a protractor baseline.
Age and grade do not measure readiness. Adjust reading or adult support to preserve the intended learning goal.
Follow the sequence
1. Practice
Practice previewGeometry: Measuring and Classifying Angles
Practice · Independent · 15 min
Read protractors and classify acute, right, and obtuse angles with structured practice.
Teaching and response guide
- Model the target skill: read a protractor from its zero-degree baseline. Use the first task as a guided example before asking for an independent response.
- Check readiness first: Identify an angle's vertex and rays and place a ray on a protractor baseline.
- Discuss an incorrect response using this distinction: Read the scale that begins at the aligned zero; the other scale may give the supplementary angle.
Watch for: Read the scale that begins at the aligned zero; the other scale may give the supplementary angle.
Check the answer criteria for each task. A supported explanation may have more than one acceptable response. These activities offer evidence to discuss; completing a sheet alone does not establish mastery.
Possible next goals
Choose the next unit when its prerequisites fit your learner.