Rekenreks are ideal for building number sense. They provide students with a concrete, physical object to help develop and deepen their understanding of numbers. Students build a strong sense of 5 and 10, learning about the relationships among numbers and operations along the way.


  • Adding and Subtracting
  • Composing and Decomposing Numbers
  • Number Sense
  • Subitizing
  • Counting


20-Bead Rekenreks

20-Bead Rekenreks

Master number relationships up to 20

100-Bead Rekenreks

Master number relationships up to 100


A wide variety of accessories are available

Learning About Rekenreks

A Rekenrek is an arithmetic frame designed to help students visualize addition and subtraction strategies. Students focus their learning on groups of 5 or groups of 10 up to 100. The Rekenrek combines features of the number line, individual counters, and base-ten models such as Base Ten Blocks. This approach allows students to think in groups of those benchmark numbers, 5 and 10.

The 20-bead Rekenrek features 2 rows, each with 10 beads. Each row is broken into 2 sets of 5 beads using contrasting colors–red and white–to help students see numbers, as well as to help them visualize how numbers can be composed and decomposed.

The 100-Bead Rekenrek version has 10 rows of 10 beads each—5 red and 5 white beads. This allows students to explore problems involving larger numbers. With the 100-Bead Rekenrek, counting is extended to 100 and easily allows students to count by 10s and to visualize the process. Now students can focus on the idea of multiples of 5 or 10

What is a Rekenrek?

Rekenreks build number sense and encourage students to subitize, visualize number relationships, strengthen counting proficiency, and use grouping to solve addition and subtraction problems. You can use Rekenreks to make groups of 5 and 10 and to teach additive strategies such as double-double strategy and near-5 strategy.


Primary Grade Activities (PreK to 2nd)


In the primary grades, students can explore Rekenreks as they model addition and subtraction. They can use addition and subtraction within 20 to solve word problems involving situations of adding to, taking from, putting together, taking apart, and comparing, with unknowns in all positions.

Here are 2 activities using Rekenreks in different contexts.

Activity Curriculum Strands Topics
Solve Word Problems Involving Comparing

Students solve word problems involving comparing by introducing and reinforcing the concept.

Number Addition and Subtraction
Make 10

Students build sums of 10, draw their models, and complete number sentences. They may refer to number cards if it will help them.

Number Addition and Subtraction

Download Rekenreks Primary Grades Sample Activity

Download a free Rekenreks activity to see how you can use the 5 E's to develop conceptual understanding.

Make Ten

Skills: Addition and subtraction strategies
Objective: Find the number that makes 10 when added to another number 1–9 and justify in a picture and equation.
From: Learn with Rekenreks Teacher Resource Guide