When teaching the importance of longitude and latitude lines, my students always like it when I have them to blow up a blue balloon (to represent the Earth), get a permanent marker and sit back to back to each other. Then:
1. I one student try to describe an area/location to the other and have the other student try to find it. When they have difficulty, I then have the class to draw the equator around the balloon.
2. Then I have them to repeat #1. This time they will find it a bit easier but still hard when they can say if the location is above or below the equator.
3. Then I have them to draw some longitude lines (and number them) on the balloon and then repeat #1. Once again it is easier but still difficult to get the same location.
4. I then have them to draw latitude lines (and number them) on the balloon and repeat #1. Still sitting back to back they should be able to have one describe the location and the other student to find the same location on their balloon.
I hope I have explained this well enough to use.