You From Jersey? What Exit?

   Robert Kaplinsky has posted an assortment of great activities, including one dealing with highway signs.  Jeff and I tweaked it a bit to make the focus on placing fractions on a number line, and tried it out with our fourth grade classes. We started with this sign:

  We had a general discussion about what the sign means, and then gave the kids some poster paper and fraction tiles and asked them to make a picture of the road.   We discussed the fact that in order to draw a picture of what this road might look like, we would need to scale a mile down to a manageable size.  Using the tiles seemed like a good idea, especially since the kids were already comfortable using them.

Beginning to map out a highway.

     You can see the "road" turned into a number line running along the bottom, using the red tile to represent one mile.  We debated whether or not to ask the kids to label all the 1/4 increments or just the ones at the exits, and eventually settled on labeling them all.

 We then explored what would happen if a mile was scaled to one inch.  You can see what happened in the top left corner of the picture.

We copied other highway sign pictures for the kids to work on.

     We have left this activity ongoing as a center/exploration and imagine extending it in some different ways, including:

• Using other units to represent one mile, such as cuisenaire rods or fraction towers.
•  Adding additional exits to existing road signs, with exits coming at increments of quarters or halves.  
• Allowing kids to create their own roads and signs.  I can imagine these roads extending down the hallway, with lots of papers taped together, stretching on for "miles and miles" with little toy cars driving up and down.

   Thanks again to Robert, and to my colleagues here at school who worked to make this idea into a reality in their classrooms.