This Instructional Activity is a part of the Lesson 1, Unit 5, Grade 7. The purpose of this activity is for students to continue interpreting signed numbers in context and to begin to compare their relative location. A vertical number line shows the heights above sea level or depths below sea level of various animals. The number line is labeled in 5 meter increments, so students have to interpolate the height or depth for some of the animals. Next, they are given the height or depth of other animals that are not pictured and asked to compare these to the animals shown. As students work, monitor for whether they are expressing relative distances in words, for example "3 meters below," or if they are expressing the same idea with notation, as in -3 meters.