By the process of elimination, students figure out the secret 3-digit number.
Students will use their knowledge of place value to ask questions that will help them figure out a secret 3-digit number.
3-digit number, place value, Ones, Tens, Hundreds
This game will help reinforce students understanding of the Ones, Tens, and Hundreds positions in three-digit numbers.
Before playing, refresh students knowledge of the positions of the Ones, Tens, and Hundreds columns. You might draw a representation of the columns and their positions on the board or a sheet of chart paper:
Hundreds Tens Ones
Then provide a series of numbers and ask random questions such as
Next, write a 3-digit number on a card or a small slip of paper. Keep the number secret from your students. Then invite them to ask yes or no questions about the digits and their positions in the number that will help them figure out what the number is. For example, if you write the secret number 467, students might ask questions such as
Go around the room and give each student an opportunity to ask a yes or no question that will help them pinpoint the digits that appear in the Ones, Tens, and Hundreds columns of the secret number. After each student asks her/his question, s/he is entitled to guess the secret number based on the information at hand.
Students might keep track of the possibilities by creating a chart that looks something like this one:
|0 1 2 3 4 5 6 7 8 9||0 1 2 3 4 5 6 7 8 9||0 1 2 3 4 5 6 7 8 9|
Students might draw an X through each number as their questions remove it from possibility.
So far we know that
With the knowledge above, the questioning continues
By the process of elimination, we now know the secret three-digit number must be 467.
When the rules of the game and the questioning techniques are clear to your students, you might give a student the opportunity to write down the secret number and respond to classmates questions about the digits that appear in the numbers Ones, Tens, and Hundreds columns.
Who was the first student to figure out the secret 3-digit number?
Lesson Plan Source
MATHEMATICS: Number and Operations
GRADES Pre-K - 2
NM-NUM.PK-2.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 3 - 5
NM-NUM.3-5.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 6 - 8
NM-NUM.6-8.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
GRADES 9 - 12
NM-NUM.9-12.1 Understand Numbers, Ways of Representing Numbers, Relationships Among Numbers, and Number Systems
MATHEMATICS: Problem Solving
GRADES Pre-K - 12
NM-PROB.PK-12.1 Build New Mathematical Knowledge Through Problem Solving
NM-PROB.PK-12.2 Solve Problems That Arise in Mathematics and in Other Contexts
NM-PROB.PK-12.3 Apply and Adapt a Variety of Appropriate Strategies to Solve Problems
NM-PROB.PK-12.4 Monitor and Reflect on the Process of Mathematical Problem Solving
GRADES Pre-K - 12
NM-COMM.PK-12.1 Organize and Consolidate Their Mathematical Thinking Through Communication
NM-COMM.PK-12.2 Communicate Their Mathematical Thinking Coherently and Clearly to Peers, Teachers, and Others
NM-COMM.PK-12.3 Analyze and Evaluate the Mathematical Thinking and Strategies of Others
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