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Grade 8s your task is to create 4 forms using light and dark and pen and ink techniques
hatching - a row of lines, all facing in the same direction. More dense and concentrated in the areas that appear darker.
cross-hatching - similar to hatching, except with the addition of criss-crossing lines.
contour-hatching - follows the contour, or curve or outline, of the object. In this case, the hatching is rounded to match the shape of the circle.
scumbling - tiny, squiggly circular lines - sort of like "controlled scribbling"
stippling - placing many, many dots on the paper to indicate shading. Probably the most time consuming of all the methods, but creates some neat effects.
Read more:
http://www.art-is-fun.com/drawing-techniques-creating-value-in-pen-and-ink-drawings.html#ixzz1t2id8ifV