The purpose of this activity is for students to use what they know about what 10 looks like to estimate whether a group has more or fewer than 10 images. Students then count the images to see if they estimated correctly. It is important for students to know that there is not always a right answer, particularly when the number of images is close to 10, as in the second and fourth questions. It is important that answers of both “more” and “fewer” are accepted and the emphasis is on students sharing their reasoning (MP3).

• Display the image:

  

• “Some students said they thought there were more than 10 pencils and some thought there were fewer than 10 pencils. Both are good answers.”
• Invite a student to share why they thought there were more than 10.
• Invite a student to share why they thought there were fewer than 10.
• “When groups are close to 10, it is hard to tell whether there are more or fewer than 10 without counting.”

The purpose of this activity is for students to analyze the reasonableness of estimates. It is important for students to know that there is not always a right answer, particularly when the estimate is close to the number of images, as in the third question. It is important that answers to both questions are accepted and the emphasis is on students sharing their reasoning (MP3).

• Display the last image of triangles.
• “Do you think 6 or 14 is a better guess for the number of triangles in this picture? Why?” (14 is a better estimate. I can see a 3 on the top and then there are a lot more, so there are more than 6.)

The purpose of this activity is for students to choose from activities that offer practice with number and shape concepts. Students choose from five centers introduced in previous units. Students can choose to work at any previously introduced stage of these centers:

• Shake and Spill
• Number Race
• Grab and Count
• What's Behind My Back?
• Pattern Blocks

Students will continue to choose from these centers in upcoming lessons. Keep the materials from each center organized to use each day.

• “Tell your partner about a time when you used a math tool to help you during centers. How did the tool help you?”