However, my most basic tool in my tool box is to use what I call the "Speed Limit Analogy." Basically, I use miles per hour (MPH). For example, I'll tell a student something like this...
"The speed limit to play _______ is 60mph. You are only going 40mph."
This analogy is helpful, especially for younger students, because it provides concrete information that they can relate to even if they are too young to drive. They've all been in the car with their parents.
This isn't applicable to all air issues, but it is a simple tool that I thought you might find helpful.