The table has row and column headings, relating to the content of the associated cells, down one side and along the top. The cells are each identified by marks placed at a specific location w.r.t. a grid into which each cell is divided and information is obtained by sliding a sub-panel corresponding to one grid position over the table. A label giving details of each course is stuck into each cell; these labels may be changed as required and may be covered or uncovered by the panels.
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