Solving Mysteries with Guess and Check!

Math Grades 1st Grade 4:13 Video
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Lesson Description

Learn how to use the guess and check strategy to solve math problems, just like a detective! We'll make smart guesses and check if they fit the clues.

Video Resource

How to Guess and Check Problems

Miacademy Learning Channel

Duration: 4:13
Watch on YouTube

Key Concepts

  • Guess and Check Strategy
  • Educated Guesses vs. Wild Guesses
  • Place Value (Tens and Ones)
  • Reading Comprehension in Math Problems

Learning Objectives

  • Students will be able to explain the guess and check problem-solving strategy.
  • Students will be able to differentiate between educated guesses and wild guesses.
  • Students will be able to use place value to make educated guesses when solving math problems.
  • Students will be able to solve a word problem using the guess and check strategy.

Educator Instructions

  • Introduction (5 mins)
    Begin by asking students if they've ever played a guessing game. Explain that in math, we can sometimes guess and check to find the answer. Introduce the video 'How to Guess and Check Problems' from Miacademy Learning Channel.
  • Video Viewing (5 mins)
    Play the video for the students. Encourage them to pay attention to how the presenter uses clues from the problem to make smart guesses.
  • Discussion (5 mins)
    After the video, discuss the key ideas presented. What is 'guess and check'? What makes a guess 'educated'? Why can't we just guess any number that comes to mind?
  • Practice Problem (10 mins)
    Present a similar word problem to the one in the video: 'I am a 2-digit number. I have a 2 in the ones place. I am bigger than 30 but smaller than 50. What number am I?' Work through the problem together as a class, guiding students to make educated guesses and check if their guesses fit the clues.
  • Independent Practice (10 mins)
    Provide students with another similar problem to solve independently or in pairs. For example: 'I am a 2-digit number. I have a 0 in the ones place. I am bigger than 65 but smaller than 85. What number am I?'

Interactive Exercises

  • Number Clue Game
    Write a few 2-digit number riddles similar to the examples in the lesson plan. Have students take turns reading the clues and guessing the number, explaining their reasoning for each guess.

Discussion Questions

  • What does it mean to make an 'educated' guess?
  • Why is it important to check your guess to see if it fits the problem?
  • Can you think of other times when guessing and checking might be helpful, outside of math?

Skills Developed

  • Problem-solving
  • Critical thinking
  • Reading comprehension
  • Place value understanding

Multiple Choice Questions

Question 1:

What do we do first when we use 'guess and check'?

Correct Answer: Make a guess!

Question 2:

If a number has a 7 in the ones place, what is the last number?

Correct Answer: 7

Question 3:

Which guess is better when solving a math problem?

Correct Answer: An educated guess

Question 4:

If a number is bigger than 20, can it be 19?

Correct Answer: No

Question 5:

What do you need to do after you guess?

Correct Answer: Check if it's right

Question 6:

Which number has a 3 in the tens place?

Correct Answer: 35

Question 7:

Which of these numbers is smaller than 50?

Correct Answer: 42

Question 8:

I am a two-digit number. Which one am I?

Correct Answer: 22

Question 9:

If a problem says the number is less than 100, which number can it be?

Correct Answer: 99

Question 10:

Guess and Check is like being a...

Correct Answer: Detective

Fill in the Blank Questions

Question 1:

We use the 'guess and _____ ' strategy to solve problems.

Correct Answer: check

Question 2:

An educated guess should make _____ to the problem.

Correct Answer: sense

Question 3:

The number 23 has a 3 in the ______ place.

Correct Answer: ones

Question 4:

The number 45 has a 4 in the ______ place.

Correct Answer: tens

Question 5:

A wild guess is a guess that doesn't make ________.

Correct Answer: sense

Question 6:

If a number is greater than 30, it's ________ than 30.

Correct Answer: bigger

Question 7:

We have to ______ our guesses to make sure they are right.

Correct Answer: check

Question 8:

The guess and check strategy helps you solve _____ problems.

Correct Answer: math

Question 9:

If a number is less than 5, it's ________ than 5.

Correct Answer: smaller

Question 10:

Guess and Check helps make math ________!

Correct Answer: fun

Educational Standards

CCSS.Math.Content.1.OA.A.1:Use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions, e.g., by using objects, drawings, and equations with a symbol for the unknown number to represent the problem. CCSS.Math.Content.1.NBT.B.2:Understand that the two digits of a two-digit number represent amounts of tens and ones. Understand the following as special cases:

Teaching Materials

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