Students having trouble with negative numbers?

I created this thermometer number line to print out and put on the wall of my classroom as a visual anchor chart that relates negative and positive numbers to students in a context that they already know and understand.

This number line can be printed out any size but was created at a scale of 11"W x 68"H so that it could be printed in large size at a printer or at home/work by printing it out on 8 landscape-oriented US-letter-sized papers and taping/gluing them together.