BLACK-BOARD OUTLINE
The black-board scheme, as the lesson develops, will appear as follows:
1. Meaning of Cleaning:
Cleaning is removing any foreign substance.
2. Methods of Cleaning:
(1) Scraping or rubbing away the foreign substance.
(2) Dissolving the foreign substance and then scraping or rubbing it away.
3. Household cleansing agents used in the first method:
| (1) Duster | (6) Whiting |
| (2) Brush | (7) Bathbrick |
| (3) Broom | (8) Coarse salt |
| (4) Washboard | (9) Sand |
| (5) Knife | (10) Ashes. |
4. Household cleansing agents used in the second method: