This is a summary of the three part math lesson we were fortunate to observe in Justus' Grade 5/6 classroom.

Once the class understood the problem, students worked in pairs to solve it. Many pairings were mixed pairings of Grade 5 and 6 students. Students chose their partners, as it was a common practice in the classroom.

Here are some of the student work we observed:

**Part 1: Getting Started:**

Justus made sure students were ready for the main problem by activating their prior knowledge with this simple activity.

He folded a piece of paper and asked students several questions such as:

*What happens to the square when you fold it along the diagonal?*

*How do you know the two triangles are congruent?*

*What did the second line of symmetry do to the two triangles?*

*How do you know all four triangles are congruent?*

Justus used folded paper along with the interactive white board throughout his questioning.

**Part 2: Working on It**

Justus chose a problem from a previous EQAO assessment. He ensured that students understood the problem by completing a KWC with the whole class.

Once the class understood the problem, students worked in pairs to solve it. Many pairings were mixed pairings of Grade 5 and 6 students. Students chose their partners, as it was a common practice in the classroom.

Here are some of the student work we observed:

This pair used a ruler and measured the dimensions of the polygon. |

This pair created a grid system and counted. |

This pair created congruent triangles. |

We observed many misconceptions in student thinking.

Base of the triangle is inaccurate |

Inaccurate calculation of the area of the triangle |

**Part 3: Reflecting and Connecting**

Based on his observations and the learning goal of the lesson, Justus chose several pairs to share their solution to the class. Students were invited to ask each other questions throughout this process.

**Part 3: Explicit Teaching and Feedback**

To summarize the lesson, Justus provided oral feedback to the class regarding their thinking and organization of their solutions.

Since this was a diagnostic task before their unit, Justus did not do any explicit teaching, as he plans to start tomorrow's lesson with one of the misconceptions he observed.