rekenrekButton.png
Click to open Rekenrek Tool in new window.


MAKE ME SOME SPACE VIA A TRICK FROM GREG Home | mathies Tools | Rekenrek Tool
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ExamplesFeatures of the Tool
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How-To Videos


Rekenreks are arithmetic racks used to build understanding of whole numbers, number relationships and reasoning for various operations.
Each rod has ten beads, five of one colour followed by five of another colour.

Take a screenshot of your work to share with your teacher or add to a portfolio.


Examples

Rekenrek_Seven.png

Representing


Represent numbers by sliding the beads to the left.

This shows the number 7.

Five red beads followed by two white beads helps us to see that 7 is equal to 5 + 2.
Rekenrek_SevenPlusEight.png

Addition and Subtraction


Slide 8 beads to the left on the second row.

This now shows 7 + 8 = 15.

Alternatively, ten red beads and five white beads help us to see that 15 is equal to 10 +5.

Or, if we think about the white beads on the right hand side, we can think of 15 as equal to 20 - 5.
Rekenrek_Fifteen_with_Shade.png
Use the shade to think about 15 + ? = 20.
Rekenrek_MoreRows.png
Click on the + sign to increase the number of rows of beads.
Rekenrek_FourTimesSeven.png

Multiplication


This represents 4 rows of 7 or 4 x 7.

There are 28 beads in total, so we know that 4 x 7 = 28.
Rekenrek_DecomposedProduct.png
If we look only at the red beads, we see 4 groups of 5.

The white beads show 4 groups of 2.

So, the colours help us to see that 4 x 7 = 4 x 5 + 4 x 2.
Rekenrek_CookieSolution.png

Image Import

It might be helpful to import a screencast of the question you are working on.

The rekenrek provides a powerful visual representation that could be used to support a variety of multiplication strategies.

How might you use this representation to support reasoning related to:
  • counting
  • halving then doubling (8 x 9 is 4 x 9 doubled)
  • decomposing 9 (8 x 9 is 8 x 5 plus 8 x 4)
  • using an anchor of 10 (8 x 9 is 8 x 10 minus 8 x 1)
  • another approach?
Rekenrek_Annotation Mode.png

Annotation Mode


Press the pencil icon at the top of the screen to enter annotation mode.

Make notes to explain your thinking.
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Features of the Tool

Rekenrek_PlusButton.png

Add a Row

Rekenrek_ShadeButton.png

Show Shade

Add one or two shades to the stage.
Shades can be used to hide part of the representation.
Rekenrek_PencilButton.png

Annotation Tool

Make notes or highlight various features of your representation. More details.
Rekenrek_ImageButton.png

Insert Image Button

You can insert images into the tool (as of version 1.1.1). More details.
Rekenrek_ResetButton.png

Reset

Delete all your work and return the tool to its starting state.
Rekenrek_InfoButton.png

Information

Access a link to this wiki, a How-to video, a feedback form as well as copyright details and version number.
Rekenrek_SettingsButton.png

Settings

Use this mode to adjust the bead and background colours as well as hide, delete or move rows.
The tool is also completely functional in this mode.
Rekenrek_Settings.png
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PDF Supports

mathies Rekenrek Learning Tool Tip Sheet

Rekenrek Tip Sheet
(Source: EduGAINS /Ministry Developed Resources/ Mathematics / Classroom Practices/Technology and Teaching Tools/Manipulative Use)
  • What are Rekenreks?
  • How do Rekenreks help students?
  • Sample Activities
  • Recommended Websites

Visit EDUGAINS for additional Tip Sheets.


What's New With CLIPS? There's an App for that! OAME Gazette article, March 2014

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How - To Videos

Videos are provided in two formats to allow for use on a greater variety of browsers and devices.
Exploring the Basic Functionality

Video Transcript
Not working? Try mp4 format
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