few_shots: 
Example 1:
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.


Concept/skill: 
Solve addition and subtraction word problems, and add and subtract within 10, e.g., by using objects or drawings to represent the problem.

Answer: 
No. Though this task involves addition, it does not involve any word problems.

Example 2:
Problem/activity:
Task
 Arrange the fractions in order from least to greatest. Explain your answer with a picture.
 $\frac{1}{5}, \frac{1}{7}, \frac{1}{3} $
 $\frac{2}{5}, \frac{2}{7}, \frac{2}{3} $
 $\frac{5}{6}, \frac{3}{6}, \frac{1}{6} $
 $\frac{5}{12}, \frac{8}{12}, \frac{4}{12} $

Concept/skill: 
Explain equivalence of fractions in special cases, and compare fractions by reasoning about their size.
 Grade 3 expectations in this domain are limited to fractions with denominators 2, 3, 4, 6, and 8.

Answer: 
Yes. By arranging the fractions in this problem, students learn to compare fractions by reasoning about their size.

Example 3:
Problem/activity:
Problem 1
Solve using the standard algorithm. If you get stuck, use an area model and/or the partial products algorithm to help. Then assess the reasonableness of your answer.
a.
$$5,803\times46$$
b.
$$63\times2,116$$
Problem 2
Dunkin' introduced a croissant doughnut in 2014. In the first three months of its debut, they sold 7,870 dozen of them per day. How many croissant doughnuts were sold in the first three months?


Concept/skill: 
Fluently multiply multi-digit whole numbers using the standard algorithm.

Answer: 
Yes. This set of problems involves multi-digit whole numbers because the numbers in each problem are four and two digit integers, and the mathematical calculations involved in both problems focus on multiplication. The first problem explicitly asks the student to solve its subproblems using the standard algorithm.

Now, does the following problem or activity enable students to learn the full intent of the following concept or skill?

shot_info: im_task_001477_neg_0

K

im_task_000157_pos_0

3

fl_problem_000674_pos_0

5
standard_description: Extend polynomial identities to the complex numbers. For example, rewrite x^(2) + 4 as (x + 2i)(x – 2i).
problem_activity: Activity
In this activity, students match equivalent expressions involving exponents and radicals. This is the first time they see negative rational exponents, so expect a lot of discussion around those expressions. Students will have more chances to interpret negative exponents, so it is not crucial for them to show mastery at this time.
Monitor for groups who reason about the expressions with negative fractional exponents in different ways. For example, some students may see
\(7^{\text- \frac12}\)
as
\(\left(7^{\text-1}\right)^{\frac12}\)
, while others will think of the expression as
\(\left(7^{\frac12}\right)^{\text-1}\)
. Ask these groups to be ready to share their reasoning during the discussion.
Launch
Arrange students in groups of 2. Give students a few minutes of quiet think time before asking them to share their responses with their partners. Tell students that if there is disagreement, they should work to reach agreement. Follow with a whole-class discussion.
Conversing: MLR8 Discussion Supports.
Arrange students in groups of 2. Invite students to take turns finding a match and explaining their reasoning to their partner. Display the following sentence frames for all to see: “ ____ and ____ are equal because…” and “I noticed _____, so I matched….” Encourage students to challenge each other when they disagree. This will help students clarify their reasoning about equivalent expressions that involve exponents.
Design Principle(s): Support sense-making; Maximize meta-awareness
Student Facing
Match each exponential expression to an equivalent expression.
\(7^3\)
\(7^2\)
\(7^1\)
\(7^0\)
\(7^{\text-1}\)
\(7^{\text-2}\)
\(7^{\text-3}\)
\(7^{\frac{1}{2}}\)
\(7^{\text-\frac{1}{2}}\)
\(7^{\frac13}\)
\(7^{\text-\frac{1}{3}}\)
\(\frac{1}{49}\)
\(\frac{1}{343}\)
\(\sqrt7\)
\(\frac{1}{\sqrt[3]{7}}\)
\(\sqrt[3]{7}\)
49
\(\frac{1}{\sqrt7}\)
343
7
\(\frac{1}{7}\)
1
Student Response
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for free access to Student Response.
Student Facing
Are you ready for more?
How do we know without counting that the number of circles equals the number of squares? Because we can match every circle to exactly one square, and each square has a match:
[IMG]
[IMG]
We say that we have shown that there is a one-to-one correspondence of the set of circles and the set of squares. We can do this with infinite sets, too! For example, there are the same “number” of positive integers as there are even positive integers:
[IMG]
Every positive integer is matched to exactly one even positive integer, and every even integer has a match! We have shown that there is a one-to-one correspondence between the set of positive integers and the set of even positive integers. Whenever we can make a one-to-one matching like this of the positive integers to another set, we say the other set is
countable.
Show that the set of square roots of positive integers is countable.
Show that the set of positive integer roots of 2 is countable.
Show that the set of positive integer roots of positive integers is countable. (Hint: there is a famous proof that the positive rational numbers are countable. Find and study this proof.)
Student Response
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click here to register or sign in
for free access to Extension Student Response.
Anticipated Misconceptions
If students aren’t sure how to match the negative rational exponents, ask them if they could make an educated guess based on the other patterns they notice.
Activity Synthesis
Begin the discussion by selecting 2–3 groups to share how they matched the expressions with positive exponents. Next, invite previously identified groups to share how they matched the expressions with negative exponents. While students share their thinking, display any exponent rules referenced for all to see, such as
\(\left(b^m\right)^n = b^{m \boldcdot n}\)
or
\(b^{\text-n} = \frac{1}{b^n}\)
. It is important for students to understand that fractional exponents follow all the same exponent rules as integer exponents.


aligns: no