1. Sums and Differences Via Pattern Blocks

2. Needed for this lesson At least three sheets of the triangle graph paper available at http://math.rice.edu/~lanius/images/triangle.gi f http://math.rice.edu/~lanius/images/triangle.gi f

3. Part 1 To complete the questions from Part 1, ▫You can use the triangle paper printed from the link on the prior slide ▫You can use the applet from the website: http://ejad.best.vwh.net/java/patterns/patterns_j.shtml http://ejad.best.vwh.net/java/patterns/patterns_j.shtml Solutions are on the next slide for Part 1.

4. Sums and Differences Via Pattern Blocks Part 1. Answer the following questions. For Questions 1 – 4, write and solve the arithmetic problem described. If the yellow hexagon = 1, then the red trapezoid = _______, the blue rhombus = ________, and the green triangle = _______. 1. Adding 1 green triangle and 2 green triangles illustrates what arithmetic problem? 2. Adding 1 blue rhombus and 1 blue rhombus illustrates what arithmetic problem? 3. Adding 1 red trapezoid and 1 red trapezoid illustrates what arithmetic problem? 4. Adding 3 green triangles and 2 green triangles illustrates what arithmetic problem? 1/2 1/6 + 2/6 = 3/6 = 1/2 1/61/3 1/3 + 1/3 = 2/3 ½ + ½ = 2/2 = 1 3/6 + 2/6 = 5/6

5. Problems from Part 2 of the handout For each problem illustrate the process of addition or subtraction with the manipulatives on separate sheets of paper (triangle paper). Record the mathematics symbolically beneath each step in the process of addition or subtraction.

6. Video: Adding Fractions Video 1 st part of sums and differences (addition) After watching the video complete # 3, check your solution process on the next slide

7. Solution to number 3 Be sure to show the equivalent fractions as that is key to moving to solving problems with the algorithm

8. Video: Subtracting Fractions Video 2 nd part of sums and differences (subtraction) After watching the video complete # 6, check your solution process on the next slide

9. For subtraction problems, be sure to show the “take away” process on the first fraction Solution to number 6

10. Video: Changing the Whole Video 3 rd part of sums and differences (whole changes to 4 hexagons After watching the video complete #’s 9 - 12, check your solution process on the next slides

11. Solution to 9 and 10

12. Solution to 11 and 12