acute
angle
background
black
blackboard
centimeter
chalk
chalkboard
closeup
college
color
degrees
design
drafting
drawing
drawn
education
engineering
equipment
flat
geometry
item
knowledge
lay
learning
length
line
markings
math
mathematics
measure
measuring
number
object
protractor
ruler
school
science
shape
stationery
study
supplies
table
teach
tool
top
triangle
university
view
work