As I was going through security at the Kansas City airport a while back, a TSA official asked me to wait so he could check my suitcase by hand.  This was the third time in three trips through security that I had been stopped, so I was getting a bit ticked off (and starting to feel like a marked man).   After he looked my bag over, the fellow politely explained, “I’m sorry I had to hold you up. Your iPod speaker was lying vertically, and we couldn’t see what it was. If you lay it flat in the suitcase, you probably won’t get stopped again.”

This little interaction took only a few seconds, but it removed every ounce of my grumpiness, and better, it has helped me move through security much more quickly. In fact, my suitcase hasn’t been hand checked since.  Simply by explaining why he was doing what he was doing, the TSA guard made me feel better about what he was doing, and at the same time he gave me some valuable information.

What this TSA official did tapped into something that I think is fundamental with most of us. We want to know why.  Spend 30 minutes with a toddler, and you’ll quickly learn that “why” is one of her or his favorite words.  When we get older, we might stop asking the question as much as we did when we were younger, but we still want to know why.

Explaining why doesn’t take much time, but it satisfies a genuine and deep-seated need for most people.  By taking just a few seconds to explain why, we move away from a power-tripping way of interacting (“just do it because I said so”) toward a more respectful way of interacting (“let me explain why I’m asking you to do this”).  Explaining why communicates that we have thought about others’ perspectives and needs, and decided to address them up front.

Over the past month, I’ve had the pleasure of observing many teachers as part of a project for the Teaching Channel.  Again and again in my observations, I’ve found that by simply explaining why, teachers, like the TSA official, can work a special kind of magic.

Here are just a few of the many “whys” I’ve heard teachers explain:

• “When you practice this with a partner, you be more likely to remember this.”

• “I need you to sit down, because if you sit like that on the desk, it is unsafe, and you might get hurt.”

• “When you talk about a new word from a new language, you are more likely to remember it.”

• “If you draw a picture of the new word, it can help you remember it.”

• “Let’s move to the next activity quickly so we have more time for our review game at the end of the period.”

When teachers gave these brief explanations, their students were much more motivated to act.  In one class, when the teacher explained why students were going to learn about propaganda (“we all need to know how to recognize whether the people who want to lead us are telling or stretching the truth”), students were immediately excited about the experiential learning activity the teacher had set up.

In some classes, teachers got their kids fired up for learning by asking them to explain why they thought a topic was important. When students come up with their own answer to the question why, it is especially powerful.

And explaining why has an additional major benefit. To explain why, we have to ask and answer the same question for ourselves:  “Why am I teaching this?  Why should students learn this?”

When we think deeply about why we are teaching something, and we come to a clear understanding of a subject’s importance, we often teach with a lot more conviction and passion … and students learn better.

Explaining why is encouraging, respectful, and motivating. It fulfills a basic need, and it helps us tap into our passion for a subject.  It only takes a few seconds, but it is a powerful habit to adopt.  Why not explain why for every request or suggestion we make?

I would go so far as to say that if we can’t explain why, if we don’t deeply understand why we are teaching something, we are likely wasting our students’ precious time.