Number Sense
Count By 2s
Count By 2's Song
Use this song to help students hear and practice skip counting by twos in a steady rhythm.
Math Songs and Videos
This section is ready for MP4 files placed in the video folder next to this HTML file. Each card includes a built-in thumbnail, a short description, and an embedded video player for students.
Skip Counting
Count By 3s
Count By 3's Song
Play this during number pattern practice so children can listen, clap, and count by threes together.
Operations
Addition Song
Addition Song
Use this song to reinforce joining groups, counting on, and basic addition vocabulary.
If your MP4 filenames are different, update the three
src="video/..." values in this section to match the files you place in the folder.
Unit 1: Counting & Number Sense
In this unit, students build early number fluency by counting in order, counting backward, and recognizing that numbers follow patterns. They also begin to understand that each number represents a quantity.
Lesson 1: Counting to 20
Counting means saying numbers in order. Each number is one more than the number before it. When children count objects correctly, they are learning that every object gets one number name. This is called one-to-one correspondence.
1 → 2 → 3 → 4 → 5 → ... → 20
If you count five apples, you do not say numbers randomly. You point to each apple one time and say one number for each apple. That helps you know the total amount.
Big idea
The last number you say when counting tells how many objects are in the group.
Lesson 2: Counting Forward and Backward
Counting forward means moving to bigger numbers. Counting backward means moving to smaller numbers. This matters because forward counting connects to addition, and backward counting connects to subtraction.
Forward: 5 → 6 → 7 → 8 | Backward: 8 → 7 → 6 → 5
Students should notice that numbers always keep the same order. They can move forward by one or backward by one. A number line helps make this idea visible.
Lesson 3: Numbers to 120
Numbers keep going far beyond 20. As students move toward 120, they begin to see repeating patterns in the ones place and the tens place. These patterns prepare them for place value understanding.
... 98, 99, 100, 101, 102 ...
When students move from 99 to 100, they see an important shift. The pattern does not break. It grows into a new group. This is one reason number charts and spoken counting practice are both useful.
Unit 2: Place Value
This unit introduces the structure of our number system. Students learn that larger numbers can be organized into tens and ones, which makes counting, comparing, and calculating much easier.
Lesson 1: Understanding Tens
A ten is a group of 10 ones. Grouping objects into tens helps students count faster and see structure in numbers. Instead of counting every single item one by one, they can count whole groups.
10 ones = 1 ten • 20 = 2 tens • 30 = 3 tens
This lesson helps students notice that 10 is not just a number to memorize. It is also a group size. That group size becomes the foundation for place value.
Lesson 2: Tens and Ones Together
Two-digit numbers are made from tens and ones. The digit on the left tells how many tens there are. The digit on the right tells how many ones there are.
23 = 2 tens + 3 ones • 47 = 4 tens + 7 ones
Students need repeated visual practice with grouped tens and loose ones so they do not think the digits are just separate symbols. They represent actual amounts.
Lesson 3: Comparing Numbers
When comparing two numbers, students should first compare the tens. A number with more tens is greater. If the tens are the same, then they compare the ones.
45 > 32 • 18 < 21
This kind of comparison moves students beyond memorizing symbols. It helps them explain why one number is bigger or smaller.
Unit 3: Addition Concepts
Addition begins with joining groups and understanding that the total grows when more is added. Students should see addition with objects, spoken language, and number relationships.
Lesson 1: What is Addition?
Addition means putting groups together. When you combine two groups, the total becomes larger. Students should connect addition symbols to real actions, such as joining blocks or counters.
2 + 3 = 5
At first, children should see and touch what is happening. Later, they can imagine the groups mentally. That movement from concrete to abstract is the core of strong early math instruction.
Lesson 2: Counting On
Counting on is an efficient addition strategy. Instead of starting from 1 every time, students start with one number and count up. This helps them solve problems more quickly and understand number relationships.
5 + 3 → Start at 5 → 6, 7, 8
Children should practice hearing and saying the count-on sequence out loud. This strengthens mental addition and prepares them for fluency.
Lesson 3: Making 10
Making 10 is a powerful strategy because 10 is an easy number to work with. When students know how many more are needed to make 10, they can solve many addition problems more efficiently.
8 + 2 = 10 • 7 + 3 = 10
This strategy helps children organize numbers flexibly. It also supports future work with place value and mental math.
Unit 4: Subtraction Concepts
Students learn that subtraction can mean taking away, counting back, or finding the missing part. The goal is not only to get answers, but to understand what subtraction represents.
Lesson 1: What is Subtraction?
Subtraction means taking away from a group. If you start with a number of objects and remove some, the amount left becomes smaller.
5 − 2 = 3
Children should see subtraction happen physically first. They can begin with counters, blocks, or pictures. This helps them attach meaning to the subtraction sentence.
Lesson 2: Counting Back
Counting back is one subtraction strategy. Students start with a number and move backward one step at a time. This connects directly to backward counting from Unit 1.
9 − 3 → 8, 7, 6
When children count back, they should say each number clearly and track each step. This keeps subtraction connected to number order instead of guessing.
Lesson 3: Relationship to Addition
Addition and subtraction are related. If students know one addition fact, they can use it to understand a subtraction fact. This helps them see math as connected ideas, not isolated rules.
5 + 3 = 8 • 8 − 3 = 5
This relationship supports fact families and helps students check their work. It also develops flexible mathematical thinking.
Unit 5: Word Problems & Thinking
In this unit, students learn to slow down, understand a story, choose an operation, and explain their thinking. The goal is comprehension plus reasoning, not just answer-getting.
Lesson 1: Understanding Word Problems
Word problems are short stories that use numbers. Students need to understand what is happening in the story before they solve it. They should identify whether something is being added, taken away, or compared.
Sara has 3 apples. She gets 2 more apples. How many apples does she have now?
- Read the story carefully.
- Find what is happening.
- Choose addition or subtraction.
- Solve the problem.
Lesson 2: Acting Out Problems
Acting out a problem helps students make the story visible. They can use objects, drawings, fingers, or counters. This helps bridge the gap between words and numbers.
When students act out a problem, they can watch the amount change. This makes addition and subtraction easier to understand.
Lesson 3: Explaining Thinking
Students should be encouraged to explain how they solved a problem. Saying or showing a strategy builds understanding. It also helps teachers see what a student truly knows.
A strong explanation may include the numbers used, the operation chosen, and the steps taken. Even simple sentences matter.