TEACHER: Stephanie, can you explain or give another example about what
Daquan is talking about?
STEPHANIE: Um, I think so. I think that if 1 9 is 10, then 10 90 has to
be 100. Is that right?
TEACHER: Yes! Now, it seems like we have created a list that uses multiples
of 10 to get to 100. I’m wondering if you know any other ways to make 100.
ANDREA: Do you mean like using money? Cuz, I know that 25 cents and
75 cents is equal to $1.00.
TEACHER: Yes, that is what I was thinking about. How do we write that on
this chart? What would the number sentence be?
ANDREA: 25 75 100.
DAQUAN: I’m thinking about something. I think we could add a whole
bunch to that list because 99 1 is 100 and 98 2 is 100. It keeps going.
TEACHER: You all have had some really good ideas for our charts on ways to
make 100. We are going to play a game that uses the ideas we have talked
about today. When we meet with the rest of the class, I want you to share
some of the ideas we have just come up with. These ideas will help you with
the game.Practicing the Game
We play the game more than once to allow students to move from a trial-and-
error approach to eventually developing their own efficient strategies. During the
first game, I tend to join the groups and just listen in on their conversations. I
record the strategies students are sharing with their partners as well as how they
are solving their problem. I make note if a student is referring to the strategy
charts and whether a student is strategically choosing digits that get close to 100
or whether the digit selection is random. I keep these conference notes to guide
the math discourse at the end of class as well as to prepare for the next time we
play Close to 100 and for my lessons about addition strategies (see Figure 14–1 on
page 120). These conference notes help me guide math conversations and allow
me to prepare for my struggling students.
Facilitating Students’ Strategies
I carefully choose children to share during our discussion time. When listening in
on their conversations, I seek out students who can offer a strategy, a success, or
a challenge they faced that may help others when playing the game. This can be
an opportune time for a struggling learner to participate, having a specific prob-
lem or thought to share.
Lightbulbs Happen