Tim Slater, CAPER Center for Astronomy & Physics Education Research, tslater@caperteam.com
Notwithstanding unexpected technical difficulties, I can remember the only time I’ve seen an astronomer intentionally teach for an hour without support from a writing board or a projector, computer, overhead transparency, or slide carousel; if you haven’t guessed it already, it was Harvard’s astronomy historian, the legendary Professor Owen Gingrich. So, we are taking it as an initial boundary condition that compassionate ASTRO 101 professors are going to use some visual support as a consistent strategy to get students information about your class. I’m not advocating any particular commercial tool; however, so that I have a shorthand notation for the general concept of some projected visual, I’ll hereafter use the commonly recognized abbreviation for MS PowerPoint, PPT.
We already know that you definitely don’t want use PPTs that have too many words, too small of figures, distracting transitions and animations, or insufficiently contrasting colors. You’ve endured too many of those yourself at professional science conferences. But, the question at hand really is what about your PPT will help improve your course evaluations? In other words, what will enhance students’ perception that you want to help students learn and that you follow an organized pathway? Fortunately, purposefully designed PPTs can dramatically help here.
As a first step, let’s review the basic rules of what does and does not help on a PPT. You might be thinking to yourself that you already know all of these things, but a quick tour through your building peaking in on other professors’ classes or wandering through scientific conference presentations should remind you that we can all forget the basics too often.
When faculty conduct surveys of what students do and don’t like about their professor’s PPT slides, they universally plea for professors to stop reading their PPTs to students. Really. Beyond that, consider the following:
Students DON’T like | Students DO like |
Too many words | Short phrases to copy |
Animated images | Easy to read graphs |
Unnecessary animations | Slowly increasing complexity of graphs |
Inconsistent format | Short video clips |
Too many colors | Consistent use of colored font for emphasis |
Here is a place where a review of your materials from a confidential, critical friend can help. A critical friend is the one-person you can depend on who will take time to quietly let you know when you have spinach stuck in your teeth or that you embarrassingly mistyped something in that ranting Department-wide email-memo you are about to send. This person does not necessarily need to be at your institution, and perhaps it is better that they are not. But it needs to be someone you respect as an equal as well as a confidant. If you don’t have a critical friend, you need to start nurturing such a relationship so you have someone with which you can exchange your PPTs with to check for problems one of you might have missed.
The basic time-tested guidelines for PPT your critical-friend should check are:
- No hard to see colors
- No more than six lines of text
- No more than six words per line
- No complete sentences
- No adjectives
- No punctuation
The problem with projecting complete sentences is that students have been long conditioned to write down everything on the PPT, no matter how much you beg them to do otherwise. This includes the capital letters starting the sentence, illustrative adjectives & adverbs, and punctuation at the end. We promise you that you do have the unexpectedly large amount of your limited each week available to allocate toward teaching your students how to effectively and efficiently take notes in addition to teaching astronomy. You could staunchly maintain that college students should already know how to take notes and it isn’t your responsibility to teach them how, but then you’ll likely demonstrate to your students that you aren’t actually interested in helping them learn. In other words, a wise professor wouldn’t unnecessarily provoke sleeping bear on this one, especially if the bear also completes end of course evaluations.
The notion of avoiding complete sentences on your PPT is part of the broader teaching strategy not overwhelming students. You probably wouldn’t be surprised if we reminded you that learners cannot learn from a spouting fire hose of information drenching them with as many facts as possible.
Although the PPT-experts say you should avoid unnecessary pictures, we would argue otherwise. PPTs that only contain bullet points are as monotonous as some of those memorable professors you had in graduate school. Pictures, even if gratuitous, serve to break up the boredom potential. Regardless, you should always talk about the images you project. Unlike you, novice astronomy students do not readily know what an image is or what is important about it. Students also won’t have any sense of scale, even if a tiny legend is embossed across the bottom. We’ll talk about where to find pictures for your PPT and how best to use them later in this chapter. However, we need to talk about organized systems to get information to your students using PPT a bit more.
A perennial question among professors is whether or not to provide students with photocopies of your PPT, or if they should be provided online. The first order argument for distributing them early is that students can allocate their scarce class time attention to annotating the PPTs rather than furiously taking complete notes of their own. There are obvious advantages to this, not the least of which is ensuring you actually have your notes done more than 60-seconds before class starts. This also means that students who miss class or didn’t successfully copy down all of the PPT’s information have a back-up information system.
A contrasting perspective is that students won’t be motivated to come to class if the PPTs are available elsewhere. We have to agree with the students on this one; if the only reason students have to come to class is to get information to memorize from the PPT, why go to class at all? The numerous bloggings on this website are specifically designed to counteract this notion: Your class time should be so well organized and carefully designed to be so incredibly valuable that your students wouldn’t imagine missing it in their wildest dreams. If that’s not motivation enough to keep reading this book, we don’t know what would be!
If you do decide to distribute the PPT to students, we recommend that you strategically remove key information that students need to fill in. Many professors find providing what we affectionately call Naked-PPT to be highly effective. More formally known in the formal science teaching literature as “guided notes”, these are PPT with key information removed and replaced with a blank line for students to complete themselves.
PPT Displayed for Class | PPT Given to Students |
Definition of a Planet | Definition of a Planet |
1. orbits a star | 1. orbits a _____ |
2. enough mass to become spherical | 2. enough _____ to become spherical |
3. dominant object in its orbit | 3. dominant object in its _____ |
The underlying thinking here, confirmed by systematic education research, is that the process of students’ actively dressing the Naked-PPT during class will keep students more attentive. Moreover, changing your PPT into Naked-PPT is takes just a few seconds. First, complete and save your PPT presentation that you’ll be presenting in class. Second, save your final presentation a second time with a new name, adding –Naked.ppt to the end of the name. In this Naked-PPT version remove one or two vital pieces of information from some of the slides. As a word of _______ here, don’t go overboard and remove too much information. You only need to add a few blank lines here and there to make strategy this work like a charm. Removing too much information will make students perceive you are trying to trick them into coming to _______ by withholding information they need to succeed, which they will resent and report when they fill out your end-of-class _______ forms. Finally, distribute this Naked-PPT version to your students instead of the version you present during class. It works with images too!
The process of creating fill-in-the-box images is surprisingly easy. All we have done to create the example shown is insert rectangle shapes over some of the targeted words and filled them with white.
Another strategy engaging teachers use is to slowly increase the amount of information on their PPT. Like the potentially provocative label Naked-PPT, in the old days professors would call this strategy by an equally lewd name, the ‘stripping transparency.’ The strategy then was to cover most of your projected information with an opaque piece of paper, and slowly reveal information as it was needed by the students.
The thinking in those days past, which is still applicable today, was that students would hurriedly write down everything on the screen before listening to anything the professor had to say and, in the process, miss the first half of the professor’s lecture. This is because most students can not listen and write at the same time, so the tactic was to limit what students had available to copy at any one time. Today, the strategy is to use the Animate function in most PPT computer programs to slowly dispense information. Adopting some version of this yourself is probably a wise choice for your presentations.
Definition of a Planet | Definition of a Planet | Definition of a Planet |
1. orbits a star | 1. orbits a star | 1. orbits a star |
2. enough mass to become spherical | 2. enough mass to become spherical | |
3. dominant object in its orbit |
Not only does this work well for bullet lists, but it also works well when teaching with images.
No matter how you use PPT, most professors find creating PPT to be an enormously time consuming task that effectively crowds out the more important aspects of teaching students to love astronomy. This is especially true if you are a perfectionist. The truth is that students don’t notice or appreciate whether or not your slides are perfect. We recommend that you adopt the perspective that 80% good is good enough. This isn’t so you have extra time to get to the golf course; instead, we want you to use all your available teaching-innovation energy to implement the interactive teaching strategies in the other pages on this blog.
You might be surprised to learn that nearly complete PPT sets already exist for your class. Most book publishers have already paid someone to work really hard creating PPT sets for each chapter (they’ve also created test-item libraries, among other valuable resources). Typically, these PPTs already use images from your selected book and have the most important vocabulary included. If this isn’t enough, there are also PPT repositories online for all topics that are uncovered by Internet searches. Moreover, you can even use PPT sets designed from other books. If you don’t know where to find these, call your book’s publisher and marketing representative who will enthusiastically share the many resources they’ve created. By all measures, none of these PPTs you’ll find are close to perfect, nor are these tightly aligned to the specific teaching you want to do. These are, however, sufficiently good starting places to adapt to your own teaching, especially if you adopt“80% good is good enough so there is ample time to improve other parts of class” thinking.