Tuesday, July 31, 2012

I failed to put all the top beads on the right side when I took the photograph.  I noted it was important to establish the norm that all the beads should be on the right end of the string as the problem begins. The importance of this is that students learn that once the beads move from the right they become "in play" as they slide them from the right to the middle or left.

The suggestion is that the beads are moved in clusters whenever possible to do so.  To promote subitization by modeling sliding the beads in groups instead of counting them as individuals. Kinders would start with only 5 beads so that they can solidify the number relationships from zero to five.

When ten beads are used it is strongly suggested to use only two colors so that the focus is on five and ten.  Advanced students' Rekenrek can be extended to 40 beads which I will be doing with my second grade math class.  The emphasis is thinking in groups of 5 and 10 even as the numbers get larger.

The beginning demonstration should have all beads on the right side as you are facing it. Refer to this as orientaiton or "Start Position" and constantly reinforce that "Start Point" using the top row to demo to younger students.  Inquire what students notice about the Rekenrek and encourage all possible answers whether you hear 2 colors, some red, some white, five colors of each bead, ten beads in a row etc.  Some focus questions could be..."How many red beads are on the top line?" "How many beads are there in all?"  "Do you see more red beads, or white beads?"  It was suggested that after some open ended questions, inform the student to explore or work with the Rekenrek and come up with a discovery about the Rekenrek that they can share with their classmates.

Next, have them put the beads in start position.  Tell them without touching the beads count three beads in their mind. On the count of three slide all three beads at once across the string.  Do this with several numbers to encourage the movement of the beads in one push across the sting.  Okay more later....


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