Place Value Chart vs Number Divider

Experience grouping and ungrouping in our decimal number system with this interactive place value chart. Touch the chart to create tokens and move them around with your finger. Is this always possible? Remove tokens by moving them to the top of the chart. Shake your iPad or iPhone to remove all of them. Some activities supported by this place value chart: - How can you create large numbers using the least number of tokens? - How can you remove tokens quickly without shaking the device? - What happens if a token is moved from the hundreds to the ones? And what happens if you first move it to the tens place and then to the ones? This brand new version features new options to show totals, both as a number and in written english. Furthermore it is possible to use it for decimal fractions. The educational design of this interactive place value chart has been developed by Prof. Ulrich Kortenkamp (Didactics of Mathematics, University of Potsdam, Germany) and Prof. Silke Ladel (Didactics of Primary Education, Mathematics, Saarland University, Germany). It supports the development of mental concepts for place values in decimal systems and targets elementary and primary and lower secondary education.

Discover the world of divisibility in a whole new way! With this intuitive app, you’ll learn the basics of division with and without remainders and discover the divisors of a number. • Visualize numbers and their divisors through arranged tiles • Experiment with different arrangements and change the divisors • Instantly recognize whether a number is divisible • Save important discoveries in your personal archive • Adjust the display to your needs • Ideal for students, teachers, parents, and math enthusiasts • Perfect for active discovery-based math lessons and learning at home This app turns understanding divisors and division into an exciting discovery process through research tasks. The clear, streamlined user interface enables you to understand mathematical relationships by directly experimenting. Here are some examples of tasks that can be tackled actively on various levels of difficulty with the app: Explore the number 8. Change the divisor. What does it mean when the divisor is displayed in red? What does it mean when it is green? Select the number 9. Find all its divisors. Then, describe how you went about the search and what you discovered. Take the number 14 and divide it sequentially by 2, 3, 4, 5. Note your discoveries. What do you notice? Examine the divisors of the number 16. Each divisor has a partner. What do you notice about these divisor pairs? Try finding divisor pairs for other numbers as well. Investigate the numbers 15, 16, 17, 18, 19, and 20 one by one. Which of these numbers are divisible by 2? Why? Formulate a hypothesis. Explore the numbers 8, 9, and 10. Find all divisors for each number and compare them. When comparing the divisors of two numbers: Is the larger number always the one with more divisors? Take the number 24. Systematically find all its divisors. Think about and explain how you can quickly find all divisors. Find numbers that only have two divisors. Explore prime numbers: Investigate the numbers from 10 to 20 for their divisors. Which numbers have exactly two divisors? Can a number have only one divisor? Justify your answer. Find numbers with particularly many divisors. What do you notice? Compare the number of divisors for the numbers 12, 24, 36. What do you notice? Can you find other numbers with a large number of divisors? Common divisors: Investigate the numbers 18 and 24. Which divisors do both numbers have in common? What is the greatest common divisor? Develop a strategy for finding the greatest common divisor of two numbers. Investigate square numbers: Examine the square numbers 1, 4, 9, 16, 25. What do you notice about the number of their divisors? Investigate numbers divisible by 3 and list them. What do you notice about the digits of these numbers? How can you tell if a number is divisible by 3 without calculating? Pick a number and find all its divisors. Multiply two divisors together each time. What do you find? Explain and justify your discovery.