There is a number on each card.
The operation sign stands between the cards.
Work through the cards in order and write the result on the question card.
Example: 40 + 25.
First add the tens: 40 + 20 = 60, then the ones: 60 + 5 = 65.
So the question card gets a 65.
The number filled in shows the solution.
Example
For parents
What does this exercise practice?
Confidently work out addition and subtraction up to 100, also with three numbers.
Common pitfalls
With three cards the third one is often forgotten. Pointing a finger at the card being worked on helps.
How to practice at home
Draw two cards, roll an operation sign and work it out together.
Related: What does multiplying mean?, Secret Card