Adding and subtracting is much easier with these beadstrings! Each string has 20 beads, in groups of 5 red beads and 5 white beads. 10 strings in the set.
Rekenrek Student Bead String to 100, 10 Strings - Didax
Student Beadstring 1-100: Set of 10 with Round Beads
Student 1-20 Beadstring – Shopedx
What is a Bead String? - Answered - Twinkl Teaching Wiki
What is a Bead String? - Answered - Twinkl Teaching Wiki
Rekenrek Student Bead String to 100, 10 Strings - Didax
What is a Bead String? - Answered - Twinkl Teaching Wiki
Rekenrek Bead String to 20, Set of 10 - Didax
Edx Education Student 20 Beadstrings - (Pack of 10 Counting Bead
Student 1-20 Beadstring – Shopedx