A few months ago, I posted about how to clean old whiteboards. Of course, most MIT classrooms don’t have whiteboards — they have chalkboards. And there is one really, really cool thing you can do on chalkboards that you can’t on whiteboards: make dotted lines.
from the ancient days of hs geometry
from 14.02
from 14.03
from 8.033
I learned how to make dotted lines over the summer that I lived in Evan T. 19’s room, where he installed chalkboards on one of his walls. (I talk about this more in the whiteboard post.) If we were in the same room, I would tell you that I could teach you how to draw dotted lines in about 20 seconds, and you’d succeed 99.999% of the time. But alas, I cannot teach you in person, so here is a how-to in blog form c:
infographic made using chalk and dotted lines :o
Step 1. Grip your chalk correctly. Hold your chalk about 1–2 inches (2.5–5 cm) from the tip of the chalk. (You’ll need to be further back if you have wide chalk.) When learning, I find that it’s easiest to grip it even further back, perhaps 3+ inches (7.5+ cm) from the tip. I like to use the grip below, in which I have three fingers pursed around the piece of chalk.
i keep three fingers around the chalk like so
side view of grab. there are still 3 fingers around the chalk
Step 2. Angle your chalk at a small angle (theta) down from the perpendicular. The correct angle is somewhere between (0^circ) and (45^circ), but you may need to experiment with what
