The purpose of this activity is for students to compare three-digit numbers based on their understanding of place value. They are invited to explain or show their thinking in any way that makes sense to them. A number line is provided. Students may revise their thinking after locating the numbers on the number line, or they may choose to draw diagrams to represent their thinking. During the Activity Synthesis, methods based on comparing the value of digits by place are highlighted.

For the last problem, students persevere in problem solving as there are many ways to make the inequalities true but students need to think strategically in order to fill out all of them. In particular, 810 can be used in the first, second, or fourth inequality but it needs to be used in the fourth because it is the only number on the list that is larger than 793.

• Display  .
• Display .
• “Decidimos que esta afirmación era verdadera. ¿Cómo podemos usar la forma desarrollada de estos números para justificar lo que pensamos?” // “We decided that this was a true statement. How does the expanded form of these numbers help justify our thinking?” (We can see the value of each place, so we can compare each digit.)
• Invite previously selected students to share how they compared numbers without drawing diagrams or using the number line.

The purpose of this activity is for students to learn Stage 2 of the Greatest of Them All center. Students use digit cards to create the greatest possible three-digit number. Each student draws a card and writes that number as a digit on the recording sheet. Each student does this three times, to make a three-digit number. Once a digit is placed, it can’t be moved. Students compare their numbers using  >, <, or =. The player with the greater three-digit number wins the round.

Students should remove cards that show 10 from their deck.

• Select a group to share a comparison statement. For example: and .
• “Observé que los compañeros tenían afirmaciones de comparación distintas para los mismos números. ¿Cómo pueden ser ambas verdaderas?” // “I noticed that partners had different comparison statements for the same numbers. How can they both be true?”
• “Si tomo un 8, ¿en dónde lo debo ubicar y por qué?” // “If I draw an 8, where should I choose to place it and why?” (I would put it in the hundreds place since it’s almost the greatest number I could draw. I might not get 9. With 800, I have a good chance for my number to be greater than my partner’s.)