Problems come in a few shapes: joining, taking away, putting together, and comparing.
Step 1: Let's Learn
Read it, or press Listen and follow the words.
Draw before you decide
Draw the bars for what you know. The picture shows which piece is missing.
Compare problems are different
In a compare problem nothing joins and nothing leaves. Two amounts sit side by side.
Bar models make the choice obvious
Draw the whole as one long bar and the parts as sections of it. If you know the whole and one part, the missing part comes from subtracting. If you know both parts, add to find the whole. The drawing decides the operation for you.
Do not trust keywords alone
Children are often told "altogether means add" and "left means subtract". These work often enough to be dangerous. "Tom has 5 more than Ana, and Tom has 12" contains "more" but needs a subtraction. Read the whole situation and picture it; do not hunt for a magic word.
Answer in a sentence
End with a full sentence: "There are 35 apples left." A bare number does not show you understood what the number means. It also forces you to check that your answer actually answers the question that was asked.
Step 2: Try It Yourself
Tap and try it out.
First amount and Second amount
38
25
In all
63
38 and 25 make 63.
Ana
46
Leo
29
17
46 is 17 more than 29.
Step 3: Watch an Example
One step at a time.
Watch Ana Pick an Operation
A shop had 64 apples and sold 27.
- Step 1
She draws the whole bar and labels it 64.
Step 4: Your Turn
Practice makes it stick.
The Playground
Problem 1 of 3
38 children were outside and 25 more came out. How many are outside now?
children
Comparing Collections
Problem 2 of 3
Ana has 46 stickers and Leo has 29. How many more does Ana have?
more
The Missing Start
Problem 3 of 3
After 26 more books arrived, a shelf held 71. How many were there before?
books
Which Operation?
1 of 3
52 and 39 put together. How many?
2 of 3
80 take away 46. How many are left?
3 of 3
63 and 48. How much more is 63?
Step 5: Quick Check
Show what you know.
Question 1 of 2
47 birds. 28 fly away. How many are left?
Question 2 of 2
In a compare problem, does anything join or leave?
What You Learned
- Draw the bars before choosing what to do.
- A missing whole means add. A missing part means subtract.
- In a compare problem nothing changes.