  Activity

## Multiplication with Finch

Use Finch to model multiplication problems as jumps on the number line.

## BEGINNER: Outputs Only

Required lessons: Moving & Turning

Students will explore how multiplication is a repeated addition problem by programming the Finch to repeatedly jump forward a set number of centimeters.

Steps:

1. Using a centimeter number line, place Finch’s beak at 0.
2. Code Finch to repeat (using one factor) a move forward block (using the other factor). This will make Finch “jump” along the number line to model the multiplication as a repeated addition problem.
3. Where Finch’s beak stops is the answer to the multiplication sentence.

Tip: Reduce Finch’s speed to 20% or less to increase accuracy.

Required lessons: Variables and LED screen

The same lesson above can be completed using variables and the micro:bit display! Create variables for each factor to use in the loop and move forward blocks. Then, use these same variables to display the answer on the micro:bit display.

## INTEGRATION

Introduce Division

If you have an extra 15-30 minutes to add to the lesson, challenge students to find the missing factor in a multiplication problem by jumping backward. For example, in the problem 5 x ___ = 20, students would place Finch’s beak at 20 and move backward 5 cm. How many jumps would Finch need to return to 0? Allow students time to explore by trial and error and draw their own conclusions as they work.

## STANDARDS ALIGNMENT

Represent and solve problems involving multiplication and division.
CCSS.MATH.CONTENT.3.OA.A.1
Interpret products of whole numbers, e.g., interpret 5 × 7 as the total number of objects in 5 groups of 7 objects each. For example, describe a context in which a total number of objects can be expressed as 5 × 7.

Multiply and divide within 100.
CCSS.MATH.CONTENT.3.OA.C.7
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.