Teach me once, and I'll forget. Teach me twice, and now it's set!

One thing about learning as a student myself is that one of the most important ingredients necessary for deep understanding of a topic or concept is time. Simply spending more time with a concept either by repetition of the same information or even better, by reframing the concept in a variety of approaches can help improve retention of the information. How do you think I've been able to keep all these Disney and Simpsons quotes so fresh? --Actually that's still quite a mystery to me, too, but spending thirty minutes in front of the television every night for years watching re-runs probably helped.

Now, I know time can be quite the precious commodity for teachers. So, sometimes 'spending more time on a single concept' is not so 'simply' done. That is one of the reasons why the role of teacher as a curator of information, rather than the source, is more important for this generation's students than before.

So, once you have determined which information you think requires more time in class - either because those concepts are crucial for students to build a sturdy foundation for the rest of the year or because they are the concepts you've noticed your students struggle most with - I suggest structuring your lesson to allow you to teach redundantly.

Go through the lecture once

This is your normal lecture, communicating the information mostly orally. This will be the main part of the lecture, so be sure to add all the tricks and gimmicks you'd normally use to engage your students. Encourage all questions for an engaging discusssion even if they take you off on a bit of a tangent for a short while. If you need to write things on the whiteboard while speaking, do so. Just be sure that it is clear to the students that their main focus should be on the words coming out of your mouth. Refrain from using a PowerPoint presentation at this stage in the lesson - that's in the next step.

Go through the lecture again - with visuals only

Make a brief (let's say, 5-or-so minutes) PowerPoint presentation that simultaneously summarizes and visualizes the lecture you just gave. Be creative with the visuals - make comics, use rebuses, tie in popular movie characters and celebrities! Use words only as your last resort, and limit one (or some other arbitrary small number) per slide. Alternatively, if you're not confident with PowerPoint, make posters or dioramas. Really - let the visual artist in you out and soar!

Add this rule, too: don't talk or allow the students to talk while you run through the presentation/show your posters. While it's quiet, hopefully the students can hear key words and concepts from the lecture ringing in their heads as induced by the visuals. Give time for students to jot more notes or even sketch the visual aids into their notes. Then, lastly...

Open the floor to questions

Be sure to finish with a good Q&A session to wrap up loose ends or to figure out where the loose ends are! Were some of the visuals in the PowerPoint confusing? Do they have better ideas? Were they able to interpret the visuals as you intended? Can they find any more connections between the lesson content and the visual metaphors than what you originally intended?

A variety of students can benefit from a lesson structured in this way. Those who need visuals for learning, get them. Those who don't, get extra time to process the lecture in their minds during the quiet. For everyone, the PowerPoint is a great chance to review the lecture just given.

Admittedly, this style of teaching can be quite time-consuming, both during preparation and class. Making PowerPoint slides with animations and perfectly appropriate pictures specific to your lecture can eat up hours before you know it. I would say it's a great investment still. You can always re-use your PowerPoint presentations year after year, and the ability to help your students grasp concepts better is priceless. And hey, after presenting a few lessons this way in class, how about asking your students to make PowerPoint presentations of their own for extra credit? Throw them up on the Cloud and let the students review each other's PowerPoint presentations on their own time? Have the students vote on their favorite ones? ...We can go on and on with the fun.