standard_description: Express a fraction with denominator 10 as an equivalent fraction with denominator 100, and use this technique to add two fractions with respective denominators 10 and 100. (Students who can generate equivalent fractions can develop strategies for adding fractions with unlike denominators in general. But addition and subtraction with unlike denominators in general is not a requirement at this grade.) For example, express 3/10 as 30/100, and add 3/10 + 4/100 = 34/100.
Grade 4 expectations in this domain are limited to fractions with denominators 2, 3, 4, 5, 6, 8, 10, 12, and 100.
problem_activity: Narrative
The purpose of this How Many Do You See is for students to subitize or use grouping strategies to describe the images they see.
When students notice that dots are being added on with each image, they look for and make use of structure (MP7).
Launch
Groups of 2
“How many do you see? How do you see them?”
Flash image.
30 seconds: quiet think time
Activity
Display image.
“Discuss your thinking with your partner.”
1 minute: partner discussion
Record responses.
Repeat for each image.
Student Facing
How many do you see?
How do you see them?
[IMG]
[IMG]
[IMG]
[IMG]
Student Response
Teachers with a valid work email address can
click here to register or sign in
for free access to Student Response.
Activity Synthesis
Display the first and third images.
“What changed from the first group of dots to the third group of dots.” (2 more dots were added.)
“The third group has 4 dots and 2 more dots. We can write that as ‘4 and 2’ or ‘
\(4 + 2\)
’.”


aligns: no