This case study was authored by a group from Spain. The authors were: Pedro Ramos, José Jorge Rodríguez Pérez, Cristina Miguel Araujo, Juan José López Ordóñez and Lara Villaseñor Alonso. 

The case study examines a lesson from Kanto, Japan and focuses on: 

• The didactic sequence of proposed exercises. 
• Classroom management and communication with students during the lesson. 

The video is made up of three different parts:

• Part 1: The teacher asks for the edge length of a square with surface area 5 cm^2. (00:11 – 03:46)
• Part 2: The teacher proposes the problem of finding the dimensions of a rectangle whose surface area is 11,25 u^2, knowing that the width is 6 units bigger than the height. (03:46 – 21:20)
• Part 3: The teacher proposes 6 equations with increasing degree of difficulty. The teacher proposes that the students work on their resolution and alternates some indications and the resolution of the different equations. (21:20 – 32:21)

More information can be found in the attachments with the written case study, and don't forget you can add your own thoughts and comments on the video at different timestamps, or build on the ideas that are already there.