A Double Batch of Cookies

• Display a simple pattern on the whiteboard (e.g AB pattern).​
• Ask students if they can identify or extend the pattern.​
• After each extension or suggestion of the pattern, ask students to justify their thinking.​
• Ask, How do you know that the pattern is correct?​
• Proceed by writing a different or more complicated pattern (e.g. ABC pattern) on the board and repeat the steps above.​
• Once students comprehend how to build onto existing patterns, challenge them by displaying a pattern with missing pieces. ​
• Pose the question, What piece or parts of the pattern belong in the blank section(s)? ​
• Encourage students to justify their responses and to explain their reasoning. ​
• Wrap up the activity by defining the components and rules of a pattern (e.g. the pattern core, a pattern consists of at least three repetitions or cycles).

Introduction: 

• Review with the class where we have seen math and fractions in baking so far. Is there anywhere else they see math connected to baking? 
  • You can ask for some examples of favourite recipes or things to bake, and then search for that recipe on Allrecipes. Where can we see the math there? 
• Tell children that bakers and chefs use math when they need to make more than one batch of a recipe at a time 
  • Bring up a simple recipe for pancakes on Allrecipes. Ask children to notice the number of servings it makes. Is there enough for everyone in the class to have one or two with just one batch? 
  • We can start by doubling the servings, which means doubling all the ingredients as well. Do we have enough for everyone then? 
• Lead a five-minute lesson on adding and multiplying fractions. 

Lesson (25 minutes): 

• Challenge the children to use their new fraction addition and multiplication knowledge to double the recipe you have chosen. 
  • Ask them to show their calculations in their notebooks so that you can check for a solid understanding
  • When they finish doubling the recipe, challenge them to triple the recipe.
  • When they finish tripling the recipe, have them quadruple the recipe. What do they notice when they multiply the fraction by 2, 3, or 4? Do they see any connections between the products? Can they add the different numbers in a chart?
    

    Term	Ingredient Value – (add ingredient)	Difference
    1	½ cup
    2	1 cup	+ ½ cup
    3	1 ½ cups	+ ½ cup
    4	2 cups	+ ½ cup

• When students are finished, you can check their answers and strategies as a class before moving to a new recipe.  
  • If you have Chromebooks, you can give your students some recipes you have picked ahead of time for them to double, triple, and quadruple.
• As a final challenge, tell students that they have 10 cups, tablespoons, and teaspoons worth of each ingredient. How many batches can they make before they run out of an ingredient, and how do they know? 

Conclusion (10 minutes): 

• Ask children what strategies they used to add and multiply fractions.  
• Ask children what further questions they have about fractions based on what they learned and saw today.
• Tell children that they will soon be able to read any recipe and use their fraction knowledge to make as many batches as they need.