G09B—EDUCATIONAL OR DEMONSTRATION APPLIANCES; APPLIANCES FOR TEACHING, OR COMMUNICATING WITH, THE BLIND, DEAF OR MUTE; MODELS; PLANETARIA; GLOBES; MAPS; DIAGRAMS
G09B19/00—Teaching not covered by other main groups of this subclass
G09B19/02—Counting; Calculating
Landscapes
Business, Economics & Management
(AREA)
Engineering & Computer Science
(AREA)
Entrepreneurship & Innovation
(AREA)
Physics & Mathematics
(AREA)
Educational Administration
(AREA)
Educational Technology
(AREA)
General Physics & Mathematics
(AREA)
Theoretical Computer Science
(AREA)
Operating, Guiding And Securing Of Roll- Type Closing Members
(AREA)