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|John T. Harrison|
|The "Numdrum" helps children understand addition, subtraction, and other fundamental arithmetic concepts. An alternative to the number line and the 10 x 10 number square, this "decimal helical number line" lists integers around a tube, ten to a turn, in an upward spiralling helix. Comes with a "cursor" sleeve. Watch the video; read reviews, teachers' notes, and activities; learn about suppliers and direct sales.|
|Levels:||Elementary, Middle School (6-8)|
|Resource Types:||Manipulatives, Educational Vendors|
|Math Topics:||Addition, Division, Number Sense/About Numbers, Patterns/Relationships|
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