12

Get to 100

Assessing Students’ Number Sense

Introduction

This video shows Michael Flynn first introducing the game Get to 100 from the
Investigations in Number, Data, and Space curriculum to his second-grade class and
then working with two students as they play the game (Russell et al. 2008g).
In the game Get to 100, students take turns rolling 2 multiples of 5 dice (the dice
have the numbers 5, 10, 15, and 20 on them) and moving their game pieces the
amount they rolled on a 100 chart. As they play, they record the amount they move
each time in a continuous number string. For example, if a player rolls a 5 and a 10
during one turn and then on the player’s next turn she rolls a 15 and a 10, the player’s
number string would read 5  10  15 10 (see Figure 12–1). The object of the
game is to get to 100 on the 100 chart. Once a game piece lands on 100, the player
checks that it should have landed on 100, by adding up the number string.
As students play Get to 100, they work on adding numbers, particularly
adding on multiples of 5 and 10. The structure of the game encourages students
to count by groups rather than by 1s. Students also learn about the structure of
the base ten number system and about what happens when you add on multiples
of 5 or 10 to a number.
Some students may find playing Get to 100 challenging. They might find it
difficult to navigate around the 100 chart or to keep track of where they are and
where they are moving to on the chart. Some students may not realize that their
number string should show where they are on the 100 chart and that at the end
of the game, the number string should add up to 100.Some students may have
difficulty adding 2 double-digit numbers or, even if they can add on 5, 10, or 20,
they might have trouble adding on 15 to a number. Some students may have trou-
ble adding the entire number string at the end.
As you watch the video, consider the following questions. You might want to
take notes on what you notice.

• How is the teacher using his interaction with the two students as an as-
  sessment and teaching opportunity?