Teacher presentation materials. Unit: 8.9 Putting It All Together (Grade 8). 8.9 Putting It All Together In these optional lessons, students solve complex problems. In the first several lessons, they consider tessellations of the plane, understanding and using the terms “tessellation” and “regular tessellation” in their work, and using properties of shapes (for example, the sum of the interior angles of a quadrilateral is 360 degrees) to make inferences about regular tessellations. These lessons need to come after unit 8.1 has been done. In the later lessons, they investigate relationships of temperature and latitude, climate, season, cloud cover, or time of day. In pa