Lesson Plan - Get It!
- Which plate of cookies would you rather have? Why?
You most likely said that you wanted the plate on the left, or the plate with more cookies.
- How do you know that the first plate has more cookies?
Let's go through the steps together:
- Count the number of cookies on each plate out loud, starting with the first plate.
- How many cookies are on the first plate?
- That's right; there are 5 cookies on the first plate.
- Now, let's count the cookies on the second plate. Count out loud.
- How many cookies are on the second plate?
- Good job! There are only 4 cookies on the second plate.
When you were counting, did you notice that the number 4 came before the number 5?
That is because 4 is less than (or smaller than) 5. You can also say that 5 is greater (this means more or bigger) than 4, as we can see by our plates of cookies.
Now, you are going to learn how to write number sentences that compare two unequal (different or not the same) numbers or amounts. A number sentence uses numbers and symbols instead of words and punctuation to make meaning. Just like a sentence in a story that you read or in a paragraph that you write, number sentences are read from left to right.
To put the cookies in a number sentence to show that the first plate, or the plate on the left, has more cookies, we need a symbol that means greater than.
Read this poem and think about which plate the crocodile will eat first:
"In the river lives a silly crocodile,
His name is Joe but his friends call him Lyle.
This crocodile has a tummy that always rumbles,
No matter how much he eats, it still hungrily grumbles.
So this crocodile, call him Joe or call him Lyle,
He'll gobble up anything, no matter how vile.
There is only one rule by which Lyle must abide;
He always starts eating on the bigger side."
Here are our two plates, in the same order as above:
- If Lyle the hungry crocodile is going to start eating the cookies, which plate will he eat first?
Remember, he always starts on the bigger side.
That's correct! He will start with the plate on the left because it has 5 cookies, and the plate on the right only has 4.
This picture is the same as writing the number sentence 5 > 4, which reads, "Five is greater than four."
Congratulations! You just wrote your first number sentence!
- You may be thinking, "What happens if there are more, or a bigger number, on the right?"
That is a very, very good question. Let's go back to our poem about Joe Lyle the crocodile to decide which number he would eat first:
Right, 7 is bigger than 3. Seven comes after 3 when we count. If you have 7 cookies, and I have 3 cookies, you have more cookies.
In this case, the crocodile turns toward the larger number to gobble it up first, but now the sentence changes. Since we always read number sentences from left to right, we need to start the sentence with "3 is ... "
- What can we say about 3 that makes the sentence true, and that makes the crocodile's one rule true?
Excellent! That's right, "Three is less than seven." The math statement is written as 3 < 7.
When the crocodile faces the number on the left, it means greater than. When the crocodile faces the number on right, it means less than.
Here are two videos that show you different ways to remember the greater than and less than signs, so you can start writing number sentences on your own!
Check out this rap song for a different take on the symbols: UMIGO - Greater Than Less Than (COMPARISON):
Watch Mr. Alligator come to life and chomp, chomp, chomp! (below):
Don't forget, when two numbers are the same, they are equal: =.
For example, 5 = 5:
Move on to the Got It? section for some fun practice!