How to play Integer Lift

  1. Choose a level, then press Start game.
  2. Read where the lift starts and how it moves.
  3. Tap the floor where you think it stops.
  4. Watch the lift make the trip, a floor at a time, to see if you were right.
  5. A game is twelve trips.

For parents and teachers

Negative numbers make sense when they are places: floors below the ground. Going up is adding and going down is subtracting, and the basement floors show why 3 take away 5 is minus 2. The Taking away level is the hard one: taking away a downward move is the same as moving up, so (minus 2) take away (minus 5) is 3. Ask your child to say each trip aloud as the lift moves.