How Many Floors Down?

Explicit Instruction/Teacher modeling

• Read the first half of the story aloud, pausing on each page to notice how many floors Ben is going down.
• Display the number line and model how the floors are going down, just like the numbers go down on the number line.
• Introduce the word subtraction as taking something away from something else, using the elevator going down as an example (e.g., when they go down one floor, write "10 – 1 = 9" to figure out which floor they will be on next).
• Write up an equation from the beginning of the story 10 – 1 = 9 on the board and explain that this is how we write a subtraction number sentence. Model how to read it aloud: "Ten minus one equals nine."
• Model solving the subtraction problem using the number line to show how to take one away, or jump to the smaller number.
• Explain the difference between addition and subtraction using the number line to model an addition problem.

Guided Practice

• Finish reading the story, inviting the students to act out the scene by pretending to be Ben going down in the elevator.
• Collaboratively write and solve equations to go with several more pages of the story.
• Ask students to turn and talk to answer the question: "If Ben was on the 7th floor and went down 1 floor, which floor would he be on? What might he see?"
• Share out and record the subtraction problem on the board, using the number line (or elevator buttons) to solve the problem.

Group work time

• Explain that now students will get to make their very own elevator and set of elevator buttons.
• Display the cardboard boxes and materials and go over any classroom materials expectations.
• Pair students together and explain that they will have 10 minutes to create their elevator and buttons. After 10 minutes, ring a bell to signal time for them to go down the elevator and practice figuring out which floor will be next.
• Send students to work in pairs.
• Ring the bell halfway through the work period and circulate around the room to ensure students transition to playing "elevator" and working to find out which floor will be next.