For this activity, provide students 10 scale drawings with the scale given beneath them and a ruler. Explain the concept of scale drawings, and tell students to measure the length of the these drawings in inches to find the length of the real objects. Do one problem together to show students the proper method. For example, if a drawing of a fish with a scale of 1:4 is 14 inches long, students would multiply its length of 14 inches by four to get its real length of 56 inches.
In this activity, give students scaled pictures of 10 objects in your room. This time, students will measure the lengths or widths of the drawing and the object to find the scale. Instruct students that this is essentially the same as reducing a fraction to its simplest form, and do the first drawing together. For example, if you measure the length of a drawing of a textbook at 3 inches and the length of the real book at 15 inches, it makes a ratio of 3:15, or 3/15 as a fraction. However, since three is a multiple of 15, this can be reduced to 1/5, for a scale of 1:5.
Pair off everyone in your class and give each pair five sheets of paper with different scales written on them and measuring tools. The pairs will look for, measure and make two-dimensional drawings of objects to the scales written on each sheet. Ideally, you should do this activity in an outdoor area like a playground and give each pair a measuring tape, but if one is not available, you can still do the activity in the classroom with rulers. In either case, you should match the scales you give students with the environment, using larger scales for outdoors or smaller ones for indoors.
For more advanced levels, teachers can try this scale drawing activity that involves a bit of algebra. Give students 10 scale drawings with the scales beneath them, but do not give them any rulers. Instead, the length of the real object will be given in inches, and students must find the length of the drawing using algebra. For example if the scale of a drawing of a television is 2:5 and the real length is 10 inches, it can be expressed as 2/5 = x/10. Through cross multiplication, you get the equation 20 = 5x, in which x = 4, meaning the drawing is four inches long.