few_shots: 
Example 1:
Concept/skill: 
Represent addition and subtraction with objects, fingers, mental images, drawings (Drawings need not show details, but should show the mathematics in the problem. (This applies wherever drawings are mentioned in the Standards.)), sounds (e.g., claps), acting out situations, verbal explanations, expressions, or equations.

Problem/activity:
Task
Materials
One 10-frame per pair of students (see example below)
[IMG]
Counters, 10 per pair of students
Decks of number cards 0-5 (with 4 of each number) or two 0-5 dice
Setup
This activity is done in pairs. The students sit side by side with 10-frame and deck of cards or dice. If they have cards, the cards are shuffled and placed face down in front of them.
Action
Player 1 flips a card or rolls the die. They place that many counters on the 10-frame. Player 2 flips a card or rolls the die. They place that many more counters on the 10-frame next to the counters already on the ten frame. The students count the total together.
A recording sheet can be added when the students have been introduced to equations and number sentences. For those students who can handle higher numbers, a deck of 0-10 cards and two 10-frames can be used.
This game can also be played alone.


Answer: 
Yes. This task involves representing addition with objects such as number cards and dice.

Example 2:
Concept/skill: 
Apply and extend previous understandings of multiplication to multiply a fraction or whole number by a fraction.

Problem/activity:
For each pair of numbers, determine if the values are equivalent. Explain your reasoning for each one.
a.
$$-0.25$$
and
$$\frac{1}{-4}$$
b.
$$-\left ( \frac{1}{4} \right )$$
and
$$\frac{-1}{-4}$$
c.
$$\frac{-1}{4}$$
and
$$-\frac{1}{4}$$


Answer: 
No. The expressions shown in this problem do not involve multiplying fractions with other fractions, nor whole numbers with fractions.

Example 3:
Concept/skill: 
Prove the addition and subtraction formulas for sine, cosine, and tangent and use them to solve problems.

Problem/activity:
Find the general solution for:
$${\mathrm{cos}\left({\pi\over2}+x\right)=\mathrm{tan}{\pi\over4}}$$


Answer: 
Yes. An initial step when solving for x in this problem requires the use of the addition formula for cosine on the left side of the equation.

Now, determine whether the following problem or activity can enable students to understand the concepts or skills in the provided description.

shot_info: im_task_001477_pos_0

K

fl_problem_001097_neg_0

7

fl_problem_001894_pos_0

HS_0
standard_description: Given a two-digit number, mentally find 10 more or 10 less than the number, without having to count; explain the reasoning used.
problem_activity: Narrative
The purpose of this activity is for students to consider possible mistakes when multiplying large numbers. Monitor for students who:
revise their answer after examining Kiran’s mistake.
recognize that
\(650 \times 10 = 6,\!500\)
so
\(650 \times 27\)
has to be much greater than 5,850.
can explain why Kiran should be multiplying
\(650 \times 2 \times 10\)
.
recognize that
\(20 \times 50 = 1,\!000\)
so there should be three zeros in the second partial product.
When students determine Kiran's error and make sense of his work, they interpret and critique the work of others (MP3).
MLR1 Stronger and Clearer Each Time.
Synthesis: Before the whole-class discussion, give students time to meet with 2–3 partners to share and get feedback on their response to “what parts of Kiran’s work do you agree and disagree with?” Invite listeners to ask questions, to press for details and to suggest mathematical language. Give students 2–3 minutes to revise their written explanation based on the feedback they receive.
Advances: Writing, Speaking, Listening
Launch
Display or write for all to see.
\(650 \times 27\)
Display each number in a different corner of the room:
14,000
18,000
13,000
19,000
“When I say go, stand in the corner with the number that you think is the most reasonable estimate for
\(650 \times 27\)
. Be prepared to explain your reasoning.”
1 minute: quiet think time
Ask a representative from each corner to explain their reasoning.
“Does anyone want to switch corners?”
Ask a student who switched corners to explain their reasoning.
“Now you are going to find this product and analyze some work.”
Activity
Groups of 2
5–7 minutes: partner work time
Student Facing
Find the value of the product.
[IMG]
Below is Kiran’s work finding the value of the product
\(650 \times 27\)
. Is his answer reasonable? Explain your reasoning.
[IMG]
What parts of the work do you agree with? Be prepared to explain your reasoning.
What parts of the work do you disagree with? Be prepared to explain your reasoning.
Look at your solution to problem 1. Is there anything you want to revise? Be prepared to explain.
Student Response
Teachers with a valid work email address can
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for free access to Student Response.
Activity Synthesis
Ask previously identified students to share their thinking.
Display Kiran's work.
“Why doesn’t 5,850 make sense?” (
\(650 \times 10 = 6,\!500 \)
so
\(650 \times 27\)
should be a lot larger than 6,500.)
“What makes sense about Kiran’s work?” (
\(650 \times 2 =1,\!300\)
, but he needs to multiply
\(650\times2\times10\)
.)
Display a student's solution or the image from the student solution.
“How do we know that 17,550 is a reasonable value for the product?” (Because
\(600 \times 30 =18,\!000\)
.)


aligns: no