Sydney Laughlin Part A: Standard: 4.OA.A.1 Interpret a multiplication equation as a comparison, e.g., interpret 35 = 5 × 7 as a statement that 35 is 5 times as many as 7 and 7 times as many as 5. Represent verbal statements of multiplicative comparisons as multiplication equations. Concepts in standard: 1. 2. 3. 4. 5. 6. Multiplication facts to 12. Missing Factors . EX: _ *3=12 Read and write multi-digit whole numbers using base ten numerals. Use representations to display multiplication: Array, lattice, grid, groups, repeated addition, number line, and equations. Multiplication Properties: Commutative property: When two numbers are multiplied together, the product is the same regardless of the order of the numbers. EX: 4*2=4*2 Associative: when three or more numbers are multiplies the product is the same regardless of the grouping of the factors. EX: (2*3)*4=2*(3*4) Identity: The product of any number and one is that number. EX: 1*2=2 Distributive: The sum of two numbers times a third number is equal to the sum of each addend times the third number. EX: 4*(6+3) = 4*6+4*3 Materials needed: Plastic math tiles, vocabulary index cards, pencil, paper, interview question sheet. Misconceptions of multiplication: The student may know the commutative property of multiplication but fails to apply it to simplify the “work” of multiplication. The student knows how to multiply but does not know when to multiply (other than because he was told to do so, or because the computation was written as a multiplication problem). The student under generalizes the results of multiplication by powers of 10. To find products like 3 × 50 = 150 or 30 × 50 = 1,500, she must “work the product out” using a long method of computation. The student can state and give examples of properties of multiplication but does not apply them to simplify computations. The student misapplies the procedure for multiplying multidigit numbers by ignoring place value. The student generalizes what she learned about single-digit multiplication and applies it to multidigit multiplication by multiplying each column as a separate single-digit multiplication. Thinking that the operation that needs to be performed (+, –, ×, ÷) is defined by the numbers in the problem. Part B: Interview of USIMS Student Vocabulary: Each one of these key terms will be displayed on an index card. One by one I will ask the student to explain what each term means in their own words. Each vocabulary word will be introduces with “In mathematics what does _________ mean?” Representation- Multiples- Comparison- Equation- Factors- Multiplication- Having introduced the vocabulary to the student I will move onto the computation. How many ways can you represent a multiplication equation? Using the tiles provided solve the equation 5x3. Using the representation given create a word problem for 5X3. What types of problems can be used by this representation? What does the 5 represent in the word problem? What does the 3 represent in the word problem? How would it affect the story if the numbers 5 and 3 switched places? How would it affect the answer if the numbers 5 and 3 switched places? Create a multiplication equation using the numbers 30 and 50. What do these numbers have in common with the equation 3x5? Without solving the equation can you tell me the answer? If a piece of rope is 3 times as thick as a piece of twine, which is thicker the rope or the twine? How do you know? What is the statement demonstrating? Solve the following equation: A 10 foot alligator is how many times larger than a 2 foot alligator. What type of math problem is this? What is the problem asking you to find? How did you complete this problem? Why?