- Arrange numbers - level 1
  - Arrange numbers - level 2
  - Arrange numbers - for professionals
  - Find numbers - level 1
  - Find numbers - level 2
  - Find numbers - for professionals

Place values
  - Recognize place values
  - Change place values -1-
  - Change place values -2-
  - Change place values -expert-
  - Convert texts into numbers
  - Convert texts into numbers -2-
Order
  - Predecessors and successors -1-
  - Predecessors and successors -2-
... increase & decrease
  - Practice -level 1-
  - Practice -level 2-
  - Practice -level 3-
  - Practice -expert-
Recognize number intervals
  - Practice -level 1-
  - Practice -level 2-
  - Practice -expert-
  - Practice -top expert-
Order numbers
  - Order numbers

Introduction
  - Creating Roman numerals
Roman to decimal
  - Converting -level 1-
  - Converting -level 2-
  - Converting -level 3-
  - Converting -professional
Decimal to Roman
  - Converting -level 1-
  - Converting -level 2-
  - Converting -professional-
Memory games
  - memory 1 to 10
  - memory 11 to 60
  - memory 4 to 50
  - memory 40 to 500
  - memory for experts
  - memory for champions
Order ...
  - Roman numerals -level 1-
  - Roman numerals -level 2-
  - Roman numerals -professional-

Introduction
  - Creating binary numbers
  - Recognize place values
Binary to decimal
  - With place value table -1-
  - With place value table -2-
  - Converting -level 1-
  - Converting -professional-
  - Converting -top expert-
Decimal to binary
  - With place value table -1-
  - With place value table -2-
  - With place value table -profi-
  - Converting -level 1-
  - Converting -profi-
  - Converting -top profi-
Memory games
  - memory -level 1-
  - memory -level 2-
  - memory for experts
Order
  - Successor of a binary number
  - Predecessor of a binary number
  - Combination
  - Deepen order -expert-

  - Rounding numbers
  - Rounding numbers for experts
  - Rounded up correctly?
  - Rounded down correctly
  - Rounded correctly?

Column diagram
  - Read values from diagrams -1-
  - Read values from diagrams -prof-
  - Recognize false diagrams -1-
  - Recognize false diagrams -prof-
  - Create diagrams - 1-
  - Create diagrams -prof-
  - Evaluate diagrams
Bar charts
  - Draw bar chart
  - Read bar chart
Analyze texts & diagrams
  - Visit to the realmath zoo
  - Class representative election -1-
  - Class representative election -prof-

Number sequences
  - Lay figures -level 1-
  - Lay figures -professional-
Number combinations
  - Combination lock -level 1-
  - Combination lock -level 2-
  - Combination lock -profi level 1-
  - Combination lock -profi level 2-
  - Combination lock -top profi-

Explanation
  - What is a power?
Exercises
  - Determine the base
  - Find the exponent
  - Specify the power
  - Larger or smaller
Square numbers -1-
  - from 1² to 10²
  - from 6² to 15²
  - from 11² to 20²
Square numbers -2-
  - from 1 to 100
  - from 36 to 225
  - from 121 to 400
Memory games
  - memory 1² to 10²
  - memory 6² to 16²
  - memory 11² to 20²
  - for experts only
Word problems
  - Exercise -level 1-
  - Exercise -level 2-
  - Exercise -expert level-

... with number arrows
  - Explanation of the model
  - Create addition -level 1-
  - Create addition -level 2-
  - Create addition -profi-
  - Read addition -level 1-
  - Read addition -level 2-
  - Read addition -profi-
Mental arithmetic
  - Add two numbers
  - One number is missing
  - Add to the place value
  - What is the value of x?
Calculate cleverly
  - Estimate sums
  - Use calculation advantages -1-
  - Use calculation advantages -2-
Column addition
  - Column addition -1-
  - Column addition -profi-
  - Column addition -2-
  - Column addition -top expert-
Number stars
  - Number star -level 1-
  - Number star -level 2-
  - Number star -level 3-
Arithmetic triangles
  - Arithmetic triangle - level 1
  - Arithmetic triangle - level 2
  - Arithmetic triangle - profi
Number pyramids
  - Addition pyramid -level 1-
  - Addition pyramid -level 2-
  - Addition pyramid -level 3-
  - Addition pyramid -level 4-
  - Addition pyramid -profi 1-
  - Addition pyramid -profi 2-
  - Addition pyramid -top profi-
Adding with tables
  - Table -level 1-
  - Attention! Table -profi 1-
  - Attention! Table -profi 2-
  - Attention! Table -top expert-
Competence oriented learning
  - Form sums
  - Build number wall
Apply arithmetic laws
  - Add three numbers -1-
  - Add three numbers -2-
  - Add four numbers -1-
  - Add four numbers -2-

... with number arrows
  - Explanation of the model
  - Create subtraction -level 1-
  - Create subtraction -level 2-
  - Create subtraction -profi-
  - Read subtraction -level 1-
  - Read subtraction -level 2-
  - Read subtraction -profi-
Mental arithmetic
  - Subtract two numbers
  - One number is missing
What is the value of x?
  - Difference searched
  - Minuend searched
  - Subtrahend searched
  - for professionals
  - Estimate differences
Column subtraction
  - Column subtraction -1-
  - Column subtraction -profi 1-
  - Column subtraction -profi 2-
  - Column subtraction -expert-
Number walls
  - Number wall -level 1-
  - Number wall -level 2-
  - Number wall -expert-
Word problems
  - Difference searched
  - Minuend searched
  - Subtrahend searched
  - for professionals
Advantageous arithmetic
  - Use calculation advantages -1-
  - Use calculation advantages -2-
Competence oriented learning
  - Form differences
  - Difference change -level 1-
  - Difference change -level 2-
  - Difference change -level 3-
  - Difference change -expert-

Mental arithmetic
  - ... with two numbers
Calculation chains
  - Complete the chain -1-
  - Complete the chain -2-
  - Complete the chain -expert-
Hidden numbers
  - Secret signs -1-
  - Secret signs -expert-
Arithmetic trees
  - Arithmetic tree -level 1-
  - Arithmetic tree -level 2-
  - Arithmetic tree -profi-
  - Arithmetic tree -top expert-
Magic squares
  - Adding square
Arithmetic house
  - Arithmetic house -level 1-
  - Arithmetic house -level 2-
  - Arithmetic house -level 3-
  - Arithmetic house -professional-
Tasks with brackets
  - Problem type -level 1-
  - Problem type -level 2-
  - Problem type -level 3-
  - Problem type -level 4-
  - Problem type -expert-
  - Problem type -top expert
Table problems
  - Table values -level 1-
  - Table values -profi-
  - Calculation rule 1
  - Calculation rule 2
  - Table values -champion-
Competence oriented learning
  - Form sums and differences
Text problems
  - Find the summands
  - Problems with text -1-
  - Problems with text -2-
  - Problems with text -3-

Mental arithmetic
  - ... with two numbers -1-
  - ... with two numbers -2-
Memory games
  - Times table from 2 to 9
  - Times table from 8 to 12
  - Times table from 2 to 12
Find missing numbers
  - Add what is missing?
  - What is the value of x?
  - With large numbers
  - Multiply three numbers
Arithmetic triangles
  - Triangle - level 1
  - Triangle - level 2
  - Triangle - expert
Number walls
  - Number wall - level 1-
  - Number wall - expert-
Tables
  - Partial product
  - Fill the table -level 1-
  - Fill the table -profi 1-
  - Fill the table -profi 2-
  - Fill the table -top expert-
Text problems
  - Variable task -Level 1-
  - Variable taske -expert-
Competence oriented learning
  - Form products
Column multiplication
  - Column multiplication -1-
  - Column multiplication -2-
  - Column multiplication -3-

Mental arithmetic
  - ... with two numbers -1-
  - ... with two numbers -2-
Find missing numbers
  - Add what is missing?
  - What is the value of x?
  - With large numbers
Tables
  - Find two numbers
Large numbers
  - Divide skillfully -1-
  - Divide skillfully -2-
Number walls
  - Number wall -level 1-
  - Number wall -level 2-
  - Number wall -expert-
Competence oriented learning
  - A remainder results?
  - Form quotients

Do you know the terms?
  - Know terms -level 1-
  - Know terms -level 2-
  - Know terms -level 3-
Mental arithmetic
  - ... for professional -
Arithmetic trees
  - Arithmetic tree -1-
  - Arithmetic trees -2-
Play darts
  - One dart is thrown
  - Add two darts
  - Add three darts
  - Championship -level 1-
  - Championship -level 2-
  - Championship -expert-
Basic arithmetic operations
  - order of operations -1-
  - order of operations -2-
  - order of operations -3-
  - order of operations -4-
  - order of operations -expert-
Convert texts into terms
  - Problems with text -1-
  - Problems with text -2-
  - Problems with text -expert-
Tasks formulated as text
  - Variable problem -profi-
  - Variable problem -top expert-
Competence oriented learning
  - Form products and quotients
  - Deepen arithmetic operations
  - Pinboard -level 1-
  - Pinboard -level 1-
  - Pinboard -expert-
Illustrate the laws of arithmetic
  - Distributive law -part 1-
  - Related exercise 1
  - Distributive law -part 2-
  - Related exercise 2
Apply arithmetic laws
  - Warm up
  - Apply distributive law -1-
  - Apply distributive law -2-
  - Apply distributive law -expert-

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

What is a fraction?
  - Answer part 1
  - Answer part 2
Part of a whole
  - Identify fractions
  - Create fractions
  - Fractions correct or not?
  - Estimate and draw
  - Estimate and draw -2-
  - Estimate and draw -3-
  - How much juice ...?
  - Pouring juice in a jug
  - Determing fractions -meter-
  - Create fractions -meter-
  - right or wrong?
  - Fractional part of a square
  - Fractional part - rectangle
Number line introduction
  - Fraction and number line -1-
  - Fraction and number line -1a-
  - Fraction and number line -2-
  - Fraction and number line -2a-
Part of several whole
  - Fractions several whole
Fraction as a comparison
  - ... recognize
  - ... draw
Fraction as a quotient
  - Memory game - level 1
  - Memory game - expert

Analyze fuel gauges
  - Fuel level -1-
  - Fuel level -2-
  - Adjusting the fuel gauge -1-
  - Adjusting the fuel gauge -2-
Vivid approaches
  - ... with visualization
  - ... with vivid hints
  - ... with helpful hints
  - Part of a stake
  - Part of a stake -top-
Fraction and time
  - fraction & time
  - time & fraction
  - fraction & time -profi 1-
  - fraction & time -profi 2-
  - fraction & time -expert-
Summarizing tasks
  - Fraction and quantity
  - Quantity and fraction
  - Fraction & quantity -Top-

  - ... with visualization -a-
  - ... with visualization
  - ... with vivid hints
  - ... with helpful hints
  - Length of a stake
  - Length of a stake -top-

  - ... with helpful hints
  - Stake in the ground
  - The full tank holds ...
  - Stake in the ground -top-

Vivid introductions
  - Mixed number - tutorial
  - Improper fraction - tutorial
Various exercises
  - Mixed number - exercise
  - Improper fraction - exercise
  - Go shopping
  - Go shopping -2-
  - Go shopping -3-
Memory games
  - with fifth
  - with seventh
  - with fifth and seventh

Explanation and exercise
  - Expand fractions - tutorial
  - Exercise with visualization
  - Expand with ...
  - With which number?
  - Application and exercise
  - Expand correctly?
Apply expanding
  - Three fractions of equal value
  - Find common denominators
  - Add pearls
  - Apples in a basket

Explanation and exercise
  - Exercise with visualization
  - Reduce with ...
  - Exercise on level 1
  - Variable exercise
  - By what number ...?
  - Correctly reduced?
Apply simplifying
  - Find common denominators
  - Specify pearls part
  - Apples in a basket

Test your knowledge
  - Assign fractions -1-
  - Choose a fraction -1-
  - Choose a fraction -expert-
  - Assign fractions -top expert-
  - Find fractions - expert 3-
Memory games
  - find fractions -1-
  - find fractions -2-
  - find fractions -3-
  - find fractions -4-

On the number line
  - Arrange eighths ...
  - Arrange sixths ...
Compare fractions
  - less than a half?
  - larger or smaller?
  - Between two fractions
Order fractions
  - Ordering four fractions -03a-
  - Ordering four fractions -04a-
  - For professionals only!
Applications tasks
  - Who throws better? -1-
  - Who throws better? -profi-
  - Search for good odds

Same denominator
  - Introduction with visualization
  - First exercise
  - Add three fractions
  - Application task -1-
  - Application task -2-
  - Magic square
  - Puzzler
Different denominators
  - Introduction with visualization
  - Exercise part 1
  - Exercise part 2
  - Exercise part 2 -2-
  - Exercise part 3
  - Exercise part 3 -2-
  - Increase fractions
  - One tenth more
  - Application task
  - Buying a bike
  - Recognize and add fractions 1
  - Recognize and add fractions 1a
  - Recognize and add fractions 2
  - Recognize and add fractions 3
  - Recognize and add fractions 4
  - Unit fractions
  - Unit fractions - profi
  - Fraction pyramid -level 1-
  - Fraction pyramid -level 2-
  - Fraction pyramid -level 3-
  - Fraction pyramid level 1-3
  - Fraction pyramid - profi
  - Fraction pyramid - expert
  - Fraction pyramid - champion
  - Magic square
  - Magic square -2-
  - For professionals only
Mixed numbers
  - Number plus fraction - tutorial
  - Adding two numbers
  - Adding three numbers
  - Adding two numbers - Level 2
  - Adding two numbers - Level 3
  - Word problems

Like fractions
  - ... with visualization
  - First exercise
  - Summarize three fractions
  - Puzzler
Unlike fractions
  - First exercise
  - Second exercise
  - Third exercise
  - Decrease fractions
  - One tenth smaller
  - Unit fractions level 1
  - Unit fractions level 2
  - Unit fractions profi
  - For professionals only
Mixed numbers - tutorials
  - Number minus fraction
  - Mixed number minus fraction
  - Mixed number minus number
  - Two mixed numbers
Mixed numbers - exercises
  - Exercise part 1
  - Exercise part 2
  - Exercise part 3
  - add and subtract -2-
Mixed numbers - word problems
  - subtract fom the sum
  - Word problems -2-
  - add to the difference
  - subtract from the di...
  - Word problems -3-
  - Word problems -expert-

Number times fraction
  - Illustrative introduction -01-
  - Illustrative introduction
  - Exercise part 1
  - ... as a text problem
  - ... for professionals
  - ... for experts
  - Pay attention to texts
  - Pay attention to texts -2-
Fraction times fraction
  - Illustrative introduction -01-
  - Illustrative introduction
  - ... as a text problem
  - texts for professionals
  - Exercise on level -1-
  - Exercise on level -2-
  - Exercise on level -3-
  - For professionals only
  - Puzzler
  - Tricky task
  - Pyramid -Level 1-
  - Pyramid -Level 2-
  - Pyramid -Level 3-
  - Pyramid 1 - 3
  - Pyramid -profi-
  - Pyramid -expert-
  - Pyramid -champion-
  - Three fractions -1-
  - Three fractions -2-

Divide fraction by number
  - Illustrative introduction -1-
  - Illustrative introduction -1a-
  - Illustrative introduction -2-
  - Illustrative introduction -2a-
  - Illustrative introduction -3-
Divide number by fraction
  - Number by unit fraction
  - Number by fraction
Divide fraction by fraction
  - Exercise on level -1-
  - Exercise on level -2-
  - Exercise on level -3-
  - For professionals only
  - Tricky task
Complex Fraction
  - Complex fractions -1-
  - Complex fractions -2-
Divide mixed numbers
  - ... by fractions
  - ... by numbers
  - ... by mixed numbers

... with multiplication
  - Exercise -1-
  - Arithmetic tree -level 1-
  - Arithmetic tree - Profi 1
  - Arithmetic tree - Profi 2
  - Arithmetic tree - TopProfi
  - for champions only
... with division
  - Exercise -2-
  - Arithmetic tree - TopProfi

Place value table
  - Find place values
  - Find decimals
  - Place values - variable
  - Recognize place values
Convert texts into numbers
  - Exercise -Level 1-
  - Exercise -Level 2-
  - Exercise - professional
Deepen order
  - Exercise -Level 2-
  - Exercise - professional
  - Exercise - top professional

  - Explanation with practice
  - Halves, quarters and eighths
  - Fifths, eighths to decimals
  - Arrange decimal fractions
  - Fraction to decimal
  - Decimal to fraction
  - Larger or smaller?
  - For professionals only
Memory games - part 1
  - memory - tenths
  - memory - fifths&tenths
  - memory - eighths
  - memory - fifths&quarters
  - memory - eighths&fifths
  - tricky memory

Memory games
  - memory - thirds&ninths
  - memory - ninths&tenths
  - memory - ninths&fifths
  - tricky memory

Order of decimal numbers
  - Order decimals -1-
  - Order decimals -2-
  - Evaluate diagrams
Estimating and combining
  - Arrangement Exercise 1
  - Arrangement Exercise 2
  - Between two decimals
Read off the number line
  - Recognize tenths
  - Recognize hundredths
  - Combined exercise
Draw on number line
  - Arrange tenths
  - hundredths
  - Combined exercise
read off the number line - difficult
  - Read off Profi
  - Read off TopProfi
raw on number line - difficult
  - Arrange Profi
  - Arrange TopProfi

  - ... on level 1
  - ... on level 2
  - ... for professionals

To natural number
  - ... complete -level 1-
  - ... complete -level 2-
  - ... complete -profi-
First exercises
  - Add two decimals -1-
  - Add two decimals -2-
  - Add three decimals -1-
  - Add three decimals -2-
Various exercises
  - What is the value of x?
  - same number of decimal places
  - different number of decimal places
Addition stars
  - Addition star -level 1-
  - Addition star -level 2-
  - Addition star -level 3-
Wall of numbers
  - 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 -topprofi-
Number pyramid
  - complete pyramid
Number tables
  - table -level 1-
  - table -level 2-
  - table for professionals-

First exercises
  - Subtract two decimals -1-
  - Subtract two decimals -2-
Further exercises
  - Subtract decimals -1-
  - Subtract decimals -2-
What is the value of x?
  - subtract -professional 1-
  - subtract -professional 2-
  - subtract -professional 3-
  - subtract -top professional
Wall of numbers
  - number wall -level 1-
  - number wall -level 2-
  - number wall -level 3-
  - number wall -level 4-
  - number wall -profi-
  - number wall -top profi-
Number tables
  - complete table -1-
  - complete table -2-

Diagrams
  - Evaluate diagrams
  - Evaluate diagrams -profi-
  - Evaluate diagrams -top profi-
calculation chain
  - Complete the chain -1-
  - Complete the chain -2-
  - Complete the chain -profi-
Table tasks
  - Table values -level 1-
  - Table values -profi-
  - Calculation rule 1
  - Calculation rule 2
  - Are you the best?
Secret signs
  - Decode characters -1-
  - Decode characters -profi-
Calculation trees
  - calculation tree -level 1-
  - calculation tree -profi 1-
  - calculation tree -profi 2-
  - calculation tree -profi 3-
  - calculation tree -top profi-
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-
With parentheses
  - one parenthesis
Fraction and decimal
  - Add -Level 1-
  - Add -Profi-
  - Subtract -Level 1-
  - Subtract -Profi-
  - Add & subtract -expert-

Multiply ...
  - with 10; 100; 1000; ...
  - with 0.1 ; 0.01 ; 0.001; ...
  - for professionals
Text problems - multiply ...
  - with 10; 100; 1000; ...
  - with 0.1 ; 0.01 ; 0.001; ...
  - for professionals
Set decimal point
  - set decimal point correctly
Multiply two numbers
  - ... in your head -level 1-
  - ... in your head -level 2-
  - ... in your head -profi-
  - ... in your head -top profi-
Number walls
  - number wall - level 1
  - number wall - level 2
  - number wall - profi
  - number wall - top profi

Divide ...
  - by 10; 100; 1000; ...
  - by 0.1 ; 0.01 ; 0.001 ; ...
  - for professionals
Text problems - divide ...
  - by 10; 100; 1000; ...
  - by 0.1 ; 0.01 ; 0.001 ; ...
  - for professionals
Tables
  - Zwei Werte ermitteln
Divide cleverly
  - ... on level 1
  - ... for professionals 1
  - ... for professionals 2
  - ... for top experts

Convert texts into terms
  - variable problem -1-
  - variable problem -2-
  - for professionals
Word problems
  - Bottling wine -1-
  - Bottling wine -2-
  - Bottling wine -3-
Word problems - part 2
  - Bike tour -type 1-
  - Bike tour -type 2-
  - Bike tour -type 3-
  - Bike tour -expert-

Read numbers
  - Exercise -level 1-
  - Exercise -level 2-
  - Exercise -profi-
  - Exercise -expert-
  - Exercise -expert 2-
  - Exercise -expert 3-
  - Exercise -champion-
Arrange numbers
  - Exercise -level 1-
  - Exercise -level 2-
  - Exercise -profi-
  - Exercise -expert-
  - Exercise -expert 2-
  - Exercise -expert 3-
  - Exercise -champion-
Numbers in fraction form
  - Arrange eighths
  - Read numbers
  - Arrange numbers
  - Read & Arrange

Numbers in the middle
  - Exercise -level 1-
  - Exercise -level 1-
Comparison of sizes
  - ... in fraction form
  - ... Decimal and fraction
Order numbers
  - ... in fraction form

To the whole number
  - ... complete -level 1-
  - ... complete -level 2-
  - ... complete -expert-
Table problems
  - Complete tables -level 1-
  - Complete tables -profi-
  - Calculation rule-
  - Calculation rule 2-
  - Are you the best?
Number walls -decimal-
  - number wall -level 1-
  - number wall -level 2-
  - number wall -level 3-
  - number wall -level 4-
  - number wall -profi 1-
  - number wall -profi 2-
  - are you an expert?
Number pyramids -fraction-
  - Pyramid -level 1-
  - Pyramid -profi-
  - Pyramid -top level-
  - Pyramid -champion-
Arithmetic trees
  - Arithmetic tree -level 1-
  - Arithmetic tree -profi 1-
  - Arithmetic tree -profi 2-
  - Arithmetic tree -profi 3-
  - Arithmetic tree -top expert-
Problems with absolute value
  - Calculate with ... -1-
  - Calculate with ... -2-
  - Mixed tasks -1-
  - Mixed tasks -2-
Calculating - illustrative
  - two numbers
  - three numbers
  - three numbers -2-
Arithmetic house
  - Arithmetic house -level 1-
  - Arithmetic house -level 2-
  - Arithmetic house -level 3-
  - Arithmetic house -professional-
Fraction and decimalform
  - two numbers -1-
  - two numbers -2-
  - two numbers -expert-
With calculation strategy
  - Strategy -level 1-
  - Strategy -level 2-
  - Strategy -level 3-
  - Strategy -expert-
  - Strategy -expert 2-
  - Strategy -top expert-
Problems with brackets
  - ... one round bracket
  - ... two round bracket
  - ... round and square

With powers of ten
  - ±10, ±100, ±1000
  - ±0.1 ; ±0.01 ; ±0.001
  - profi version
Powers of ten - in text form
  - ±10, ±100, ±1000
  - ±0.1 ; ±0.01 ; ±0.001
  - profi version
With decimals
  - ... in your head -level 1-
  - ... in your head -level 2-
  - ... in your head -profi-
  - ... in your head -expert-
With fractions
  - Two fractions -Level 1-
  - Two fractions -Level 2-
  - Two fractions -Level 3-
  - Two fractions -Profi-
  - Fraction times number
Number pyramids - fraction
  - Pyramid -level 1-
  - Pyramid -level 2-
  - Pyramid -expert-
With tables
  - ... skillfully fill -1-
  - ... skillfully fill -expert-

By powers of ten
  - by ±10, ±100, ±1000
  - by ±0,1 ; ±0,01 ; ±0,001
  - Expert version
By powers of ten - text form
  - by ±10, ±100, ±1000
  - by ±0,1 ; ±0,01 ; ±0,001
  - Expert version
Tables
  - Determine two values
Fraction form
  - Two fractions -level 0-
  - Two fractions -level 1-
  - Two fractions -level 2-
  - Two fractions -expert-

Adding and multiplying
  - Problem type -1-
  - Problem type -2-
  - Problem type -mixed-
Adding and dividing
  - Problem type -1-
  - Problem type -2-
  - Problem type -mixed-
Connect operations
  - for professionals only
Arithmetic trees
  -Arithmetic tree -1-
  - Arithmetic tree -2-
  - Arithmetic tree -expert-

Connect operations
  - Number-times-bracket
  - Calculation rules -1-
  - Calculation rules -2-
  - Calculation rules -expert-
  - Calculation rules -champ-

Coordinate system
  - Enter points -level 1-
  - Enter points -level 2-
  - Read points -level 1-
  - Read points -level 2-
Calculate term values
  - ... with three terms
  - ... with three terms -2-
Calculate with temperatures
  - Average temperature
  - One value is missing
Apply arithmetic laws
  - Distributive law for experts

  - irrational numbers -1-
  - irrational numbers -2-
  - irrational numbers -3-

  - practice on level 1
  - for experts
  - for top experts

Determine square roots
  - practice on level 1
  - practice on level 2
  - for experts only
Determine radicands
  - practice on level 1
  - practice on level 2
  - for experts only
Mixed exercises
  - practice on level 1
  - practice on level 2
  - for experts only
  - what is x?
Square root memory -1-
  - memory - 1 to 10
  - memory - 6 to 16
  - memory - 11 to 20
  - memory - 15 to 25
  - memory for experts
Square root memory -2-
  - memory - 0.1 to 1
  - memory - 0.6 to 1.6
  - memory - 1.1 to 2
  - memory - 1.5 to 2.5
  - memory for experts -2-

Properties of square roots
  - ... product
  - ... division
Exercises
  - Adding square roots
  - Subtracting square roots
  - Add&Subtract
  - Add&Subtract -2-
  - Multiplying square roots
  - Multiplying square roots -2-
  - Squaring square roots
  - Dividing square roots
  - Dividing square roots -2-
Apply distributiv law
  - ... of multiplication
  - ... of division -1-
  - ... of division -2-
  - mixed exercises
Apply algebraic identities
  - Identity-I & Identity-II
  - Identity-I & Identity-II expert
  - Factoring Identity-I
  - Factoring Identity-I expert

Introduction
   - 1^st pre-exercise
   - 2^nd pre-exercise
   - simplify square roots
Mixed problems
   - Simplify square roots -expert-
   - Write as a square root
   - Mixed exercises
   - Add and simplify
   - Multiply and simplify
   - Divide and simplify
Order
   - ... square roots -1-
   - ... square roots -2-
   - ... square roots -expert-