1. Middle School Math Activate
NKCES – January 14, 2013

2. Middle School Teachers Activate
Understand ratio concepts and use ratio reasoning to solve problems.
Analyze proportional relationships and use them to solve real-world and mathematical problems.

3. Developing Proportional Reasoning
Van De Walle1, Chapter 6
Identifying multiplicative situations
Selection of equivalent ratios
Comparison of ratios
Scaling with ratio tables
Construction and measurement activities
1 Van de Walle, J. and Lovin, L. (2006). Teaching Student-centered Mathematics, Grades 5-8, Volume 3. Pearson Education, Inc. pages

4. Pizza per Camper, Please!
Solve this problem without using any numeric algorithms, such as cross-products. You may want to draw pictures or use counters.
Two camps of Scouts are having pizza parties. The Bear Camp ordered enough so that every 3 campers will have 2 pizzas. The leaders of the Raccoon Camp ordered enough so that there would be 3 pizzas for every 5 campers. Did the Bear campers or the Raccoon campers have more pizza to eat?
(source: VDW page 161)

5. Pair-share to Table-team
Share your answer with an elbow partner.
Share your answer at your table.
Record at least one different way to respond to this question.

6. Reflections of your classroom
How would your students approach this problem?
Do they use a variety of approaches?
Do they draw pictures to support their understanding?
Answer-getting by using numeric algorithms (without support of thinking) may be a clue that students are simply going through the motions of following rules without applying reasoning.

7. “Mechanical Methods”
These methods do not develop proportional reasoning and should not be encouraged (or introduced) until students have had many experiences with intuitive and conceptual methods. If students are using such methods, insist they also come up with another way to find a solution.”1
1 Van de Walle, J. (2006). Teaching Student-centered Mathematics, Grades 5-8, Volume 3. Pearson Education, Inc. page 177.

8. Expanded Lesson, VDW1 Number off 1 -4 1s do problem 1,
3s do problem 3 and
4s do problem 4
Same rules - Solve this your problem without using any numeric algorithms, such as cross-products. You may want to draw pictures or use counters.

9. Terry can run 4 laps in 12 minutes. Susan can run 3 laps in 9 minutes
Terry can run 4 laps in 12 minutes. Susan can run 3 laps in 9 minutes. Who is the faster runner?
Jack and Jill were picking strawberries at the Pick Your Own Berry Patch. Jack “sampled” 5 berries every 25 minutes. Jill ate 3 berries every 10 minutes. If they both pick at about the same speed, who will bring home more berries?
Some of the hens in Farmer Brown’s chicken farm lay brown eggs and the others lay white eggs. Farmer Brown noticed that in the large hen house he collected about 4 brown eggs for every 10 white ones. In the smaller hen house the ratio of brown to white was 1 to 3. In which hen house do the hens lay more brown eggs?
The Talks-a-Lot Phone Company charges 70¢ for every 15 minutes. Reaching Out Phone Company charges $1.00 for 20 minutes. Which company is offering the cheaper rate?

11. Scaling with Ratio Tables
Read VDW1pages and walk-through Activity 6.5 a.
With a partner create a ratio table (with operations) to assist with solving c. and d.
~Resist using the standard algorithm.

12. Scaling with Ratio Tables Activity
The tax on a purchase of $20 is $1.12. How much tax will there be on a purchase of $45.50?
When in Australia you can exchange $4.50 in U.S. dollars for $6.00 Australian. How much is $17.50 Australian in U.S. dollars?
For current rates:

13. Pair-share to Table-team

14. Which rectangles are similar?
How do you know?

15. Percent – VDW1, page
1 Van de Walle, J. (2006). Teaching Student-centered Mathematics, Grades 5-8, Vol. 3. Pearson Education, Inc.

16. Tip-jar free sample from http://www.mathalicious.com/

17. Formative Assessment Notes VDW1, page 176
Do your students distinguish between proportional situations and additive or non- proportional ones?
Are they flexible in the way they attempt to solve proportions?*
Are there differences in thinking about different types of proportional situations?
Do your students understand rates, as ratios?

19. Explore --- http://mrvaudrey.com/
a.edu/
ols-for-teachers/problems-of-the-month
rning/2013/01/five_essential_schoolwide_conditi ons_for_common_core_achievement.html?cmp=S OC-SHR-TW