Patent ID: 6079983
Filing Date: 2000-06-27
Classification: G09B

Abstract:
An educational instrument comprising:a base member having a top side, a recessed portion near a corner of said base member, a plurality of numbers arranged in a matrix and being disposed and exposed in said recessed portion, an upper level, a middle level, a lower level, a first longitudinal slot disposed between a portion of said middle level and a portion of said lower level, a second longitudinal slot disposed between a portion of said upper level and a portion of said middle level, a first longitudinal groove extending through a portion of said top side and extending from said recessed portion and terminating near a first end of said base member, and a second longitudinal groove extending through a portion of said top side and extending from said recessed portion and terminating near a second end of said base member;a first cover means having a first planar member which is movably disposed in said first longitudinal slot and further having a first handle member securely attached to said first planar member and being movably disposed in said first longitudinal groove for moving said first planar member; anda second cover means having a second planar member which is movably disposed in said second longitudinal slot and further having a second handle member securely attached to said second planar member and being movably disposed in said second longitudinal groove for moving said second planar member.