发明名称 Mathematics teaching device
摘要 A mathematics teaching device wherein a display surface is divided into eight regions. The first region contains one hundred colored and numbered plaques removably mounted in ten rows. Plaques are within five color groupings and the rows are color-coded as are receiving pockets. Two regions have another set of plaques with an adjacent receiving pocket to permit simple mathematical operations to be performed therein. The other regions are marked for additional operations to be performed therein.
申请公布号 US4424039(A) 申请公布日期 1984.01.03
申请号 US19820428355 申请日期 1982.09.29
申请人 WASHBURN, JACK E. 发明人 WASHBURN, JACK E.
分类号 G09B19/02;(IPC1-7):G09B19/02;G09B1/10 主分类号 G09B19/02
代理机构 代理人
主权项
地址