This is a great visual activity to help students understand that melting point and boiling point are specific properties of matter (for example, bromine has a specific point at which it melts and boils...which is different from that of radon and water, etc.) It also emphasizes that melting point and freezing point are the same thing...the only difference is the addition or removal of energy.
All you need for this activity are the three student handouts (I copy them 1-sided) and colored pencils (red, orange, yellow, blue, and purple). Students plot the melting and boiling points of four different substances onto thermometers and color their solid, liquid, and gas sections according to the directions.
The analysis questions help students to read their colored thermometers and to notice the unique range of temperatures at which the four substances are in each of the three different states of matter of solid, liquid, and gas.
This activity accompanies a unit on the states of matter and properties of matter.
If you are teaching about temperature or thermal energy, or if you need a sub-plan or video worksheet at the ready, you may be interested in my Making Stuff Colder documentary video worksheet
Thanks for looking!