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Class Information
Number: 434/204
Name: Education and demonstration > Mathematics > Arithmetic > Apertured elements threaded on elongate means (e.g., abacus, etc.) > Elements manually placed on or removed from elongate means during use
Description: Subject matter wherein the apertured pieces are placed by hand on the wire, rod, or like means during instruction of a student.

Patents under this class:

Patent Number Title Of Patent Date Issued
8437688 Test and answer key generation system and method May. 7, 2013
7914287 System and method of teaching and learning mathematics Mar. 29, 2011
7309233 System and method of teaching and learning mathematics Dec. 18, 2007
6575754 Device and method for teaching mathematical properties associated with even and odd numbers Jun. 10, 2003
5788556 Illuminated stacked bead art toy Aug. 4, 1998
5525089 Rotatable, demountable blocks of several shapes on a central elastic anchor Jun. 11, 1996
5395245 Elastic pattern abacus and tool for changing arrangement of abacus beads Mar. 7, 1995
5302148 Rotatable demountable blocks of several shapes on a central elastic anchor Apr. 12, 1994
5176521 Educational apparatus with interchangeable task assigning template Jan. 5, 1993
4629431 Game for teaching time concepts Dec. 16, 1986

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