Rekenrek
Number · Reception–Year 3
Slide the beads. Five red and five white, so seven reads as five and two.
About the rekenrek
Ten beads to a rod, five red then five white, all pushed to the right at rest. Slide them left to count. Tap a bead and it moves across, taking the beads behind it with it, which is what a finger does to the wooden one.
The colour break at five is the whole point. A child looking at seven beads sees a five and a two and says seven, without counting one at a time. That is subitising, and it is the thing a rekenrek does that a bead string cannot.
Two rods is the classroom default: one for each hand, or one for each part of a bond. Add rods up to ten for a hundred bead frame, and the beads resize to suit so a hundred of them still fit the board.
Row counts are off by default, and that is deliberate. A number printed next to the beads answers the question the beads are there to ask. Turn them on when you want the class to check themselves.
How to use it on your whiteboard
- 1Tap a bead to slide it across, along with the beads behind it.
- 2Drag along a rod to sweep a whole row at once.
- 3Use the rod buttons to go from one rod up to ten.
- 4Push all back clears the rack; All across fills it.
- 5Tap Fullscreen so the rack fills the board.
Questions
- Why are the beads five red and five white?
- So a number can be read without counting. Seven is a full red five and two whites, and after a while children see that shape and say seven straight away. A rack with ten identical beads has to be counted every time.
- Can I make a hundred bead frame?
- Yes. Add rods up to ten, which is a hundred beads. The beads get smaller as you add rods so the rack always fits the board.
- Should I show the row counts?
- Not while you are asking. A number beside the beads gives away the answer the beads are the question for. They are useful for checking, so they are one tap away and off to begin with.