Introduction with temperature
  - Enter into the thermometer
  - Read thermometer
Form basic ideas
  - Temperature difference -1-
  - Temperature difference -2-
  - Temperature difference -3-
  - Temperature difference -profi-

Number and opposite number
  - vivid explanation & exercise
  - memory game
The absolute value
  - vivid explanation & exercise
  - memory game
Apply fundamentals
  - memory game

Number line - read numbers
  - Read integers -1-
  - Read integers -2-
  - Read integers -3-
  - Read integers -Profi-
  - Read integers -TopProfi-
  - Read integers -Champion-
Number line - arrange numbers
  - Arrange integers -1-
  - Arrange integers -2-
  - Arrange integers -3-
  - Arrange integers -Profi-
  - Arrange integers -TopProfi-
  - Arrange integers -Champion-
Number line - Recognize order
  - Recognize order -1-
  - Recognize order -2-
  - Find order -1-
  - Find order -2-
  - Find order -profi-
  - Find order -top profi-
  - Numbers in the middle 1
  - Numbers in the middle 2

Predecessor & successor
  - Predecessor & successor -1-
  - Predecessor & successor -2-
  - Predecessor & successor -profi-
Summary exercises
  - ... on level 1
  - ... for professional users
Compare numbers - absolute value
  - Size comparison -1-
  - Size comparison -2-
Order by size
  - Problem on level -1-
  - Problem on level -2-
  - for professionals
Number sequences
  - Continue the sequence -1-
  - Continue the sequence -2-
Recognize order of integers
  - ... for professionals
  - ... for top experts

Temperatures and height
  - Detect temperature
  - Detect height
  - Height and temperature -profi 1-
  - Height and temperature -profi 2-
  - Height and temperature -profi 3-
  - Height and temperature -expert-

Introduction - number arrow model
  - Exploring the rules
First Exercises
  - Add two integers -1-
  - Add two integers -2-
Wheel of fortune
  - Wheel of fortune -1-
  - Wheel of fortune -2-
  - Wheel of fortune -3-
What is the value of x ?
  - Task Level -1-
  - Task Level -2-
  - For professionals
Arithmetic triangles
  - Arithmetic triangle - level 1
  - Arithmetic triangle - level 2
  - Arithmetic triangle - profi
Number chains
  - Addition chains -level 1-
  - Addition chains -level 2-
  - Addition chains -profi-
Number walls
  - Number wall - level 1
  - Number wall - level 2
  - Number wall - level 3
  - Number wall - level 4
  - Number wall - profi 1
  - Number wall - profi 2
  - Number wall - top profi
Pyramid of integers
  - Complete the pyramid
Number stars
  - Number star -level 1-
  - Number star -Profi-
Complete tables
  - Fill the table -level 1-
  - Fill the table -Profi 1-
  - Fill the table -Profi 2
  - Fill the table -TopProfi-
Preparation subtraction
  - Word problem -1-
  - Word problem -professional-

Introduction - number arrow model
  - Exploring the rule
First Exercises
  - Add opposite number
  - Subtract an integer
Wheel of fortune
  - Wheel of fortune - level 1
  - Wheel of fortune - level 2
  - Wheel of fortune - level 3
  - Wheel of fortune - top expert
What is the value of x ?
  - Task level -1-
  - Task level -2-
  - For professionals
Number chains
  - Subtraction chain -level 1-
  - Subtraction chain -level 2-
  - Subtraction chain -profi-
Number walls
  - Number wall - level 1
  - Number wall - profi
  - Number wall - top expert
Pyramid of integers
  - Complete the pyramid
Word problems
  - Find subtrahend
  - Find subtrahend -profi-
  - Find minuend
  - Find minuend -profi-
Deepening basic knowledge
  - Basic knowledge test
Complete tables
  - Fill the table -1-

Calculation trees
  - Calculation tree - level 1
  - Calculation tree - profi 1
  -Calculation tree - profi 2
  - Calculation tree - profi 3
  - Calculation tree - top expert
Magic squares
  - Adding square -1-
  - Adding square expert
Arithmetic house
  - Arithmetic house -level 1-
  - Arithmetic house -level 2-
  - Arithmetic house -level 3-
  - Arithmetic house -professional-
  - Arithmetic house -expert-
Word problems
  - Find and add numbers -1-
  - Find and add numbers -2-
Calculation chains
  - Complete the chain -1-
  - Complete the chain -2-
  - Complete the chain -profi
Number chains
  - Arithmetic chain -profi 1-
  - Arithmetic chain -profi 2-
  - Arithmetic chain -top expert-
Complete tables
  - Table problem -level 1-
  - Table problem -profi-
  - Calculation rule
  - Calculation rule -2-
  - Are you the best?
Calculate with ...
  - absolute values -level 1-
  - absolute values -level 2-
  - absolute value tables
Simplified notation - illustrative
  - Explain strategy - model
  - three numbers
  - four numbers
  - missing number
  - missing number -2-
With calculation strategy -step 1-
  - Strategy -level 1-
  - Strategy -level 2-
  - Strategy -level 3-
  - Strategy -profi 1-
With calculation strategy -step 2-
  - Strategy -level 4-
  - Strategy -level 5-
  - Strategy -profi 2-
  - Strategy -top exert-
Problems with brackets
  - ... with one bracket
  - ... with two brackets
  - ... with square brackets
Summary test
  - Are you strong enough?

Introduction with learning environment
  - 8-page learning environment
First Exercises
  - Multiply two integers -1-
  - Multiply two integers -2-
  - What is the value of x? -1-
  - What is the value of x? -2-
Arithmetic triangles
  - Arithmetic triangle - level 1
  - Arithmetic triangle - level 2
  - Arithmetic triangle - profi
Number walls
  - number wall -level 1-
  - number wall -level 2-
  - number wall -level 3-
  - number wall -level 4-
  - number wall -Profi-
  - number wall -Champion-
Complete tables
  - Fill the table -level 1-
  - Fill the table -profi 1-
  - Fill the table -profi 2-
  - Fill the table -top expert-
Calculate with powers
  - ... for beginners
  - ... for professionals
Powers - memory games
  - memory -1-
  - memory -2-
  - memory -3-
  - memory for experts

Introduction with learning environment
  - 7-page learning environment
First Exercises
  - Divide two integers -1-
  - Divide two integers -2-
  - What is the value of x?
Complete tables
  - Find two numbers
Number walls
  - number wall -level 1-
  - number wall -level 2-
  - number wall -top expert-

Calculation trees
  - Calculation tree -level 1-
  - Calculation tree -profi 1-
  - Calculation tree -profi 2-
  - Calculation tree -profi 3-
  - Calculation tree -expert-
Basic arithmetic operations
  - Add and multiply
  - Divide and add
  - Mixed operations
Simplified notation
  - Arithmetic tree -level 1-
  - Arithmetic tree -profi-
  - Add and multiply
  - Divide and add
  - Mixed operations
  - with parentheses
  - order of operations -1-
  - order of operations -2-
  - order of operations -3-
  - order of operations -profi-
Calculate with temperatures
  - Average temperature
  - One value is missing
  - Two values missing
  - Four values missing
Math house
  - add&multiply -level 1-
  - add&multiply -professional-
  - add&multiply -expert-
  - subtract&multiply -level 1-
  - subtract&multiply -professional-
  - subtract&multiply -expert-
Basic knowledge
  - Add and multiply
  - Basic insights multiplication