PURPOSE: To facilitate the opening/closing operation of a covering without increasing its weight and to facilitate the reading of time table without rendering it difficult to install it in place.

CONSTITUTION: Seals 5 naming the day's subjects are detachably pasted to a school time table 4 printed on the rear side of a covering 3. The time table 4 may be printed simultaneously with the decorative pattern on the rear side of the covering 3. The seals 5 may be different in shape for every subject.