Developing a Keen Eye
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Video Analysis Lesson Task
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1. Introduce
The developing a keen eye video library provides teachers and coaches with a rich set of resources to support the analysis of teaching with a goal of having productive and transformative discussions about ways to promote more ambitious teaching and learning in their mathematics classrooms. The introduction to each cycle includes background information about the lesson, the teacher, and the context for the classroom video recording.
2. Goal
Establishing clear and meaningful learning goals is an essential aspect of planning for effective mathematics instruction. Teachers need focused opportunities to articulate the intended math goals of their lessons as well as the key connections students need to make in order to achieve the intended learning goal. Math learning goals should be situated within a progression of coherent teaching that promotes and deepens student understanding over time.
3. Analyze
Research shows that analysis of teaching is one of the most effective levers for improving instruction and student achievement (Roth et al., 2019). The use of short classroom video clips and keen eye protocols focus teachers' attention on ways to promote students' engagement in mathematically productive practices and key moments when students' opportunities to make progress toward the intended learning goal occur during the lesson.
4. Reflect
Reflection is an essential part of improving planning and instructional practices. No lesson is perfect and whether teachers are new to teaching or have been teaching for many years, learning and growth results from an ongoing focus on teaching from a learning stance. The final elements the keen eye video analysis reflection cycle includes opportunities to delve deeper (optional prompts to explore) and hear final reflections from the teacher in the video.
BACKGROUND & CONTEXT
INTRODUCE
Polygons: Which One Doesn’t Belong?
Students engage in an activating strategy (Which One Doesn’t Belong?) with a goal of collecting informative data about students’ prior understandings about properties of polygons and in particular, what makes a polygon regular.
This video introduces the classroom teacher and provides background information about the content of the video. In the clip, the teacher is engaging her students in a routine (Which One Doesn't Belong?) that anticipates the day's lesson. The lesson involves having students explore ways to find the sum of the interior angles of regular polygons. On the previous day, students discovered that the base angles of an isosceles triangle are congruent.
NARRATIVE & GOAL
Polygons: Which One Doesn’t Belong?
Students engage in an activating strategy (Which One Doesn’t Belong?) with a goal of collecting informative data about students’ prior understandings about properties of polygons and in particular, what makes a polygon regular.

In this keen eye video analysis cycle, students engage in a “Which One Doesn’t Belong?” routine. The routine is designed to serve as an activating strategy for a lesson involving sums of interior angles of regular polygons. Prior to watching the video, examine the shapes and generate a list of reasons why one or more of the shapes does not belong in the group. Discuss ideas you anticipate will emerge from the students in the classroom and how this routine could be used to elicit useful formative information regarding the characteristics of different polygons.
Classroom MATHEMATICS PracticES
ANALYZE
Polygons: Which One Doesn’t Belong?
Video Analysis: Round One
Prior to watching the video clip, take a few moments to review the first page of the video analysis protocol. What do you notice? How are the descriptors organized? Use the descriptors to focus your attention on the ideas embedded in the following areas of interest. Use the given facilitation guide to help you structure a meaningful and productive conversation.
Classroom Environment
Teacher
Student Engagement
Classroom Environment
E1. Collaborative structures support student-to-student interaction
E2. Norms for engagement are in place (e.g., Rights of the Learner)
E3. Evidence of safe learning environment (e.g., mistakes are used as sites for learning, students volunteer explanations)
Teacher
T1. Asks questions that elicit students thinking
T2. Encourages justification using words, symbols, and visual representations
T3. Engages students in listening to and building upon one another’s reasoning (e.g., wait time, restating, re-voicing, adding on, agree/disagree, and why)
T4. Promotes connections by focusing students’ attention on key mathematical ideas
Student Engagement
S1. Grapple with the mathematics and engage in conversations about key ideas
S2. Question one another’s thinking (engage in respectful debate)
S3. Justify, clarify, and elaborate on their thinking
S4. Discuss and compare approaches
S5. Engage in continuous refinement (and revision)
of ideas and precision of language

Students engage in an activating strategy (Which One Doesn’t Belong?) with a goal of drawing out informative data regarding attributes and relationships between angles and sides of polygons and in particular, what makes a polygon regular.
MATH Learning opportunities
ANALYZE
Polygons: Which One Doesn’t Belong?
Video Analysis: Round Two
Before watching the video clip a second time, take a few moments to examine the second page of the keen eye video analysis protocol. How are these descriptors different from those listed on page one? Use these descriptors to focus your attention on the mathematics and intended learning goal of the lesson. Identify key moments when students’ opportunities to make progress regarding the learning occurred. The given facilitation guide is designed to help you structure a meaningful and productive conversation.
Mathematical Engagement
Mathematical Engagement
M1. Teacher elicits students’ ideas and incorporates them to promote key connections related to the identified learning goal.
M2. Use of representations (student artifacts) promotes mathematical sense making and productive discourse.
M3. Learning activities promote cognitively demanding mathematics practices by students.
M4. Students have extended opportunities to describe their reasoning and what they grappled with as part of their exploration.
M5. Small and whole group conversations are purposefully structured to help students clarify and refine their ideas and make productive progress towards the math learning goal.
Students engage in an activating strategy (Which One Doesn’t Belong?) with a goal of drawing out informative data regarding attributes and relationships between angles and sides of polygons and in particular, what makes a polygon regular.
EXTENDING OUR LEARNING
Questions to Explore:
- What characteristics of polygons emerged as a result of this “Which one doesn’t’ belong routine?
- Why do you think the teacher launched her lesson with this routine?
- How did the teacher support the students in clarifying some of the misconceptions or misunderstandings that emerged during the routine?
- Why was getting the definition of a regular polygon important in terms of the lesson for the day?
REFLECTIONS FROM THE TEACHER
REFLECT
Polygons: Which One Doesn’t Belong?
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