## Monday, November 28, 2011

### Integers: Elevator Model

Students intuitively use this model to describe riding up (+) and down (-) in an elevator.  This real-life application is one some students might have encountered if they live in a large city or have visited taller buildings.  Generally problems involve starting at one floor and going up (+) or going down (-) floors to get to another location within the building.  This provides a gentle introduction to integers in a familiar format.

The Elevator Template may be laminated or placed in a clear sheet protector for student use.  Students use dry erase markers to number the starting floor.  They may then move up or down, as dictated by the problem, using a clothespin to mark the ending floor.  NOTE:  The template was purposely left unnumbered so that it works for all types of uses and ranges of numbers.

The Elevator Problems set suggests students use an elevator template to track multiple moves from floor to floor, recording each change as an integer.  Ultimately students work through these moves to identify the final floor.

Some teachers create a fictional store with special floors (e.g. 2 - Kids' Clothing, 3 - Furniture, 4 - Toys, etc.) so that students experience this real-life application of integers.  It's easy to generate integer problems using this model:  If I get back on the elevator at the 2nd floor, ride up 5 floors, then back down 1, what floor am I on now?

Challenge students to write their own Where in the building am I now? problems.