## Teacher Guide: Lesson 15.8

The Weekly Reader Connections feature on Kids' Place Houghton Mifflin Math provides your students with additional information about the topics that appear in the Curriculum Connection feature in their student books.

Point out that while Amsterdam is the capital of The Netherlands, The Hague is the city from which the government functions. The article “Whether Art or Math, Here's a New Place to See It” describes the recently opened Escher Museum located in The Hague. The article focuses on Escher's transformational, symmetry, and impossible prints as well as the virtual-reality exhibit of Escher's works.

The Word Wise activity features the vocabulary word “unique” and its Latin prefix “uni-”, meaning “one.” After discussing the meanings of a given list of words with the same prefix, students write short paragraphs containing some of these words.

If pattern blocks are available, distribute them to groups of students before introducing the Data Hunt activity. First review how to find the sum of the angles within each shape. Then ask students to place a few blocks together with complete sides touching and so that the vertices of all the shapes are adjacent. Ask students to find the sum of the adjacent angles.

Students complete the following table to discover that the sum of the adjacent angles of the shapes that form a regular tessellation is 360°. They are told that the same total number of degrees applies to the adjacent angles in a semi-regular tessellation. They use this information to help them create their own semi-regular tessellations.

Regular Tessellations
Kind of Tessellation Total Number of Degrees at Adjacent Vertices
all equilateral triangles 60° + 60° + 60° + 60° + 60° + 60° = 360°
all squares 90° + 90° + 90° + 90° = 360°
all hexagons 120° + 120° + 120° + = 360°