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: 
Understand that by similarity, side ratios in right triangles are properties of the angles in the triangle, leading to definitions of trigonometric ratios for acute angles.

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


Answer: 
No. This problem does not directly teach how side ratios in right triangles lead to definitions of trigonometric ratios. Instead, it involves solving a trigonometric function.

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

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HS_0
standard_description: Explain why addition and subtraction strategies work, using place value and the properties of operations. (Explanations may be supported by drawings or objects.)
problem_activity: Narrative
The purpose of this activity is for students to use their knowledge of base-ten diagrams and place value to make sense of a written method. They describe how numbers, words, and equations can be used to represent the steps they have used with other representations (MP2). Students will explore other ways to use equations, including the standard algorithm, in future grades. Although some grade 2 students may begin to use recording methods like the standard algorithm, it is important to encourage students use the methods that make the most sense to them.
Required Materials
Materials to Gather
Base-ten blocks
Launch
Groups of 2
Give students access to base-ten blocks.
Display Elena’s work.
“Take a minute to make sense of Elena’s subtraction.”
1–2 minutes: quiet think time
“Discuss Elena’s work with your partner.”
1–2 minutes: partner discussion
Share and record responses. Highlight responses that describe the numbers Elena is subtracting and how Elena shows decomposing units.
Activity
“Elena is finding the value of
\(726-558\)
. Use base-ten blocks or a base-ten diagram to show Elena’s steps. Then finish Elena’s work. If you have time, work together to show a different way Elena could use numbers or equations to show her steps.”
7 minutes: partner work time
Monitor for student examples that record in a way similar to Elena, but use numbers to show the value of each place.
Student Facing
Elena’s thinking:
Step 1:
[IMG]
Step 2:
[IMG]
Step 3:
[IMG]
Use base-ten blocks or a base-ten diagram to show Elena’s steps.
Finish Elena’s work to find the value of
\(726-558\)
.
What is another way you could use numbers or equations to show subtracting by place to find the value of
\(726-558\)
?
Student Response
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Advancing Student Thinking
If students rely on one way to show subtracting by place with numbers or equations, consider asking:
“How did Elena represent the value of each digit in 726 and 558?”
“What is another way you could represent the value of the digits and show subtracting by place?”
Activity Synthesis
Display a student representation of Elena’s steps with a base-ten diagram and 1–2 other representations that use numbers and equations.
“How are these representations the same? How are they different?” (They all show decomposing a hundred and a ten before you subtract. They all show subtracting hundreds from hundreds, tens from tens, and ones from ones. They use different ways to represent each unit. One uses base-ten diagrams, one uses numbers and words, and one just represents the value of each place.)


aligns: yes