Calculation Triangle 1.3

This virtual manipulative offers a valuable tool for fostering flexible arithmetic thinking through an interactive medium.

Watch a demonstration of the application here: http://www.youtube.com/watch?v=iN3b20F6UC8

The core of the tool is a calculation triangle divided into three fields, each capable of holding tokens. The sum of the two adjacent fields is displayed on each edge of the triangle. This setup facilitates exploration of numerical relationships and operations.

The functionalities include:

• Using touch input to generate tokens within a field and to transfer tokens between fields.
• Removing tokens from the triangle to delete them.
• Closing the shutter to conceal a specific field.
• Swiping over a number to hide or reveal it.
• Shaking the device to clear all tokens from the triangle.

While this virtual manipulative does not provide predefined tasks, it serves as a flexible platform for constructing puzzle problems for peer learning or modeling and solving existing cases. Suggested activities include:

• Determining the missing numbers in the triangle.
• Estimating the number of tokens in hidden fields.
• Exploring how numbers change when adding or removing tokens from fields.
• Examining the effects of moving tokens between fields.
• Investigating what combinations of odd numbers are possible within the model.
• Analyzing relationships between the sums on edges and total token quantities.
• Assessing whether all numbers can be generated, or if restrictions apply.