“A Time for Telling” is the title of one of my favorite papers of Dan Schwartz (Professor of Education at Stanford). In it, he argues that lecture isn’t all bad. We complain that lecture (or “direct instruction” in ed-speak) doesn’t result in a lot of learning for our students. This has been shown again and again, in a lot of studies. But it’s pretty hard to completely eradicate lecture from our universities (or high schools, etc.) — it’s a pretty efficient way of communicating information. But if students first struggle with the ideas and concepts, then they’re prepared to learn from it. This is called Preparation for Future Learning.

For example, you could imagine (and it’s been shown) that students who first invent the idea of density (by being given the task of coming up with a way to describe how many clowns there are per square foot at a circus) will be better able to answer a question about the density of water than, say, a student who was just given the formula for density and shown a worked problem using gold. And a recent study by Schwartz shows just that, that those students who first invented the solution were better able to transfer the idea to a new situation. He writes:

Direct instruction is important, because it delivers the explanations and efficient solutions invented by experts. To gain this benefit without undermining transfer, direct instruction can happen after students have engaged the deep structure, per the Invent condition. [The students who invented the solution on their own] performed just as well on a subsequent test of word problems about density and speed. Direct instruction becomes problematic when it shortcuts the appreciation of deep structure. Across conditions, students who encoded the deep structure of the clown problems were twice as likely to transfer. It is just that fewer students in the Tell-and-Practice condition encoded the deep structure, because they had received direct instruction too soon.

Similarly, he later cites a study that found:

For example, college students learn more from lectures and readings when they first work with relevant data compared to when they write a summary of a chapter that explains the same data .

In some instances, he says, it is useful to just receive direct instruction because the goal is to build rote, routine skills. But in math and science, this isn’t the case:

In math and science, instruction cannot exhaust all possible situations. Transfer and adaptation are important. Although automaticity is important for some facts such as “2 x 3 = 6,” real situations rarely come with formulas attached, so students need to learn to recognize the relevant deep structures. Moreover, the cumulative curricula of math and science mean that students should build a base of knowledge on deep structures from which future learning can grow and adapt.

But teaching this way brings up the problem of assessment:

In the current milieu of high-stakes testing, standardized assessments largely measure routine expertise; namely, efficient recapitulation. If educators want students to become adaptive, innovative citizens who keep learning through changing times, current assessments do not fit. A better fit would map students’ trajectory towards adaptive expertise. Ideally, assessments would examine students’ ability to transfer, particularly for new learning. Such assessments would include resources for learning during the test (for example, a simulation that students can freely manipulate).


There was an interesting post, and comment thread, over at Built on Facts — on How to Be a Good TA. I’ve been wanting to respond to it for two weeks and have been too busy. It is interesting that this discussion came up just as I was forwarded a great article about TA Training — Growing a Garden without Water: Graduate Teaching Assistants in Introductory Science Laboratories at a Doctoral/Research University (Luft et al, Journal of Research in Science Teaching, vol 41, pp 211-233, 2004). That article delves into the dearth of training giving to graduate TA’s, who bear a large brunt of the work of communicating science to undergraduates [I’ll send you a copy if you ask]. They write:

In the past 3 decades there has been a rising concern about the instructional support afforded to Graduate TAs, and an acknowledgment by faculty that expertise in teaching does not occur instantly in higher education.

No kidding. Even faculty don’t often get this kind of training. And then they’re supposed to teach the next generation of worker bees. (One of the exemplary training programs is called Preparing Future Faculty). TA’s are called on to make all sorts of decisions about their courses (curriculum, what concepts to emphasize, how to evaluate students) and faculty aren’t guiding them very much. Faculty aren’t often well-informed about undergraduate education reforms, anyhow, which suggest that there are better ways to teach and assess students how we were traditionally taught.

The blog post from Built on Facts, in some ways, exemplifies these problems. I have no doubt that Matt is a great TA. He understands that it’s important to engage students in the process of learning. But many of his comments suggest that being a great TA is just about doing traditional instruction the best that you can. Here is what Matt said about his extensive experience as a graduate TA:

What (students) need in recitations is only so much theory as is needed for an understanding of the concept, with lots of worked example problems. Lots of them. Do them as interactively as possible, so that instead of just working through the problems yourself in front of sixty glazed-over eyes the students are actively involved in figuring things out. …

Put real thought into how you present your lectures. What seems beautiful and elegant to you might be obscure and overly complicated to a new student. Try to be clear with concepts and buttress each new idea with a concrete example problem. A real one, not a toy problem that’s orders of magnitude easier than what they’ll face on the homework.

He also suggests giving students extra practice in working problems by giving quizzes and review sessions.

I think a lot of these methods would work if there was good evidence that lectures work. But so far, the evidence suggests that students don’t learn by telling, they learn by doing. As long as you’re up there in front of the blackboard, you’re stuck in a classroom structure where information is supposed to travel from teacher to student. I don’t think that’s the best approach, based on the evidence. Get the students talking to each other, working through problems, discussing and arguing. Then act as their “guide on the side” (not the “sage on the stage”) to help them learn. You can’t teach anybody anything.

Now, I’m really not slagging on anything that Matt’s saying (or any of the other good suggestions in the comments of his post), just that the initial structure of the teaching environment he’s using is flawed. For instance, I can’t argue that it’s good to give clear explanations, to think about your lectures in advance, and to give example problems. I love his suggestion of giving quizzes — research shows that the act of trying to recall information increases your memory of it (even if you don’t get the answers), so taking as many tests as you can is a really good thing. But the “good lecture” techniques only go so far. Students plead for us to give them example problems often because they want to see something that “looks like” the homework so that they can follow it as a recipe.

The comments to Matt’s post suggest that at least the better students don’t want those boring example problems, though — like Matt says, they want “real” problems — interesting, tough problems that get them engaged in solving it. I’ve seen that desire in our physics majors here as well. What would be great is if we could really model to students how we go about solving such a problem — taking wrong turns, thinking back to worked examples, looking at limiting behavior, etc. But that takes a very long time, and is hard to do justice in front of a class.

One idea that I’ve found really compelling is called Preparation for Future Learning. The idea is that sometimes there is a time for telling (for the “theory” part of the presentation, tying things together, giving out facts), but it is after a student has already struggled with the ideas. One way to do this is to give them a canonical problem and ask them to come up with the solution. For example, ask biology students to come up with a strategy for eagle conservation. That’s a huge, open-ended problem (they don’t have to be that unstructured) but after students come up with a bunch of (poor) strategies, they are better equipped to hear and understand a lecture about conservation techniques.

TA’s aren’t well-trained and teaching is undervalued

But when would a TA learn these kinds of techniques to teach?  The article I mentioned at the top of this post (about TA training) argues that it’s not enough to know the content (in this case physics) — you also have to have Curricular Knowledge (instructional methodologies) and Pedagogical Knowledge (how to take the content of your particular discipline to the learner).  And graduate TA’s are taught neither of these — they’ve been prepared for research careers, for the most part.  Teaching is often seen as a lower-tier calling than research.  Thus, TA’s aren’t rewarded for working on their teaching, and their faculty mentors aren’t well prepared to help them in these endeavors.  TA’s feel that teaching is important, but an interest in teaching doesn’t really help their professional development as scientists.

Here is a faculty’s comments on the lack of importance of teaching for a TA, from that paper:

Sydney did think that teaching  was important, but there is a reason that it is not emphasized. He goes on to add that at the graduate student level it is perceived as being more prestigious to hold an RA appointment instead of a TA appointment. At the faculty level, research productivity is important in the yearly reviews, not teaching. Faculty may talk about the importance of teaching, but during the department reviews the focus is on research and funding. At the national level, grants are funded for research and not teaching. When grants are funded, they pay more for RAs, not TAs. Sydney pauses again and states that it is clearly a cultural thing.

TA training is poor

In keeping with these cultural expectations, TA training meetings aren’t sufficient to teach such a complicated and difficult task as teaching. Here is one TA’s comments on the usefulness (or lack thereof) of weekly training meetings, from that paper:

The staff meetings address what the lab is about. They are necessary, but are not done well.
Some TAs just like to talk and so we listen to them and they take up so much time. I just
don’t get a good view of what the lab is about from the staff meetings. I’ll ask a
question . . . and the laboratory coordinators can’t answer the question and I get frustrated.
I know that they try really hard, but it’s not exactly what I would want. I guess I need
more clarity than the other TAs and the 2-hour staff meeting is just not an efficient use of
my time. I end up going to Monday lab before I teach my sections to really get a sense of
the lab.

TA’s are left on their own

One other quote reminds me a lot of what Matt said about his teaching, since it sounds like he was pretty much on his own as he decided what to cover in recitations:

The lack of faculty involvement was also evident when GTAs discussed their preparation for teaching each laboratory. No GTA indicated seeking out the assistance of faculty members or even the laboratory coordinator when planning for their classes. Instead, as Samie stated, she often “. . . read through the laboratory manual, making sure that I understand the order of things
and what it’s asking. I interpret the lab, reword things, make the objectives clear, and think
of ways to introduce it to students and think over what I want to lecture on in the
laboratory. “

These sorts of decisions are fairly complicated for a beginning teacher to make!

The article concludes quite strongly:

In this study, GTAs and laboratory coordinators who were involved in preparing GTAs had limited opportunities to enhance their instructional abilities. The constraints of the working environment often led GTAs to make intuitive decisions, or decisions based on their own experience as students; thus their practices were often disconnected from the literature base in education.

The title of this article, ‘‘Growing a Garden without Water,’’ represents the expectations and  potential of GTAs in the absence of adequate support to facilitate their growth. GTAs have an  essential role in universities and colleges, but without proper instructional support they may not  achieve their potential. Furthermore, it is estimated that by the year 2014, 500,000 new professors  will be teaching American college students (Jones, 1993). Many of these professors will have served as GTAs. Improving the education of future students depends on the thoughtful, careful, and purposeful training of future faculty members. To meet the needs of the community, the garden must be properly tended by involved caretakers, and it will yield its fruits.

They say that rewards and incentives should be given for good teaching, and TA training programs should draw on the research base in education that informs us how we best learn to teach science.

I didn’t come up with that title.  That’s the title of a lab report turned in by a disgruntled physics major after the obligatory upper-division laboratory.  It’s kinda famous in the physics circuit.  Read it.  It’s funny.

Quotable quote:

Check this shit out (Fig. 1). That’s bonafide, 100%-real data, my friends. I took it myself over the course of two weeks. And this was not a leisurely two weeks, either; I busted my ass day and night in order to provide you with nothing but the best data possible. Now, let’s look a bit more closely at this data, remembering that it is absolutely first-rate. Do you see the exponential dependence? I sure don’t. I see a bunch of crap.
Christ, this was such a waste of my time.

I just sent this link to some of my colleagues who are starting to discuss upper-division labs at the university.  What do we want students to get out of them?  What are our goals?  I love the above lab report (have you not read it yet?  Go read it!  It’s short) in part because it seems to sing the truth of what’s broken in a lot of these labs.  We give students shoddy equipment and ask them to go and confirm something that we’ve known to be true for over 100 years.  They write it up.  It’s just as cookbook as when we ask elementary students to measure the temperature of boiling water.  But don’t we expect more from students at this level?  Shouldn’t they be able to apply critical thinking skills and do true inquiry science by the time they’ve undergone hundreds of hours of instruction in physics (or any science)?  Shouldn’t they have a working thermos?

We remember these great teachers who have taught us so much about the world. But did they really? Some educators firmly believe that you can’t teach someone anything — rather, they have to learn it for themselves. A great teacher is someone who helps make that happen. A great teacher is a facilitator of learning more than an explainer. I’ve often wondered about this, since I certainly remember the great explainers from my past. Did they really teach me nothing? Are great explainers like televisions of education — entertaining and interesting but we don’t actually retain what they try to channel into our brains? I do think this might be the case. When I’ve actively struggled with something already, and just can’t put two ideas together in the right way, a great explainer can help me make the connection that I’ve failed to make. But if I haven’t already struggled with that material, then the explanation is cool and beautiful, but quickly slips through my grasp. In EducationLand, this is called Preparation for Future Learning, or PFL. In PFL we make students struggle with an idea so that they’re prepared to listen to a lecture or to learn whatever material we want them to learn.

I just posted a new episode of my Science Teaching Tips podcast in which longtime educator Modesto Tamez shares some thoughts about how he helps students make ideas their own, so that students learn for themselves. It’s called, you guessed it, Nobody’s Ever Taught You Anything.

Posted from the PHYSLRNR listserv.  This resource looks very nice, useful and well-organized.  You can browse by topic (looking for a teaching activity on atomic physics?) as well as a wealth of other resources (click on PER-Support to look for assessments or how to use active engagement in the classroom).

The AAPT, through COMPADRE has just launched the Physics Source; its digital library portal
for introductory physics courses.

The purpose of the “Source” is to catalog quality resources that are appropriate for introductory physics teaching and make them easily available to teachers of these courses. With your help, I hope that we
can make it our “source” for introductory physics teaching resources.
Please consider doing the following:

1) Remember to use the site when looking for intro phys information.
2) Improve the site by rating content and sending us critiques or
suggestions for improvement.
3) Suggest resources you use but could not find in the site.
4) Suggest resources that you have authored/developed and that are not
in the site.
5) Consider having COMPADRE host your content if it is currently
hosted at an unreliable server.

A new study at Stanford finds that using everyday language helped students learn. The results are only preliminary, since it was a small study and they don’t have a lot of data on students’ english language proficiency, but it is still an interesting and promising bit of research. An excerpt from the Stanford Report tells us:

Usually, elementary school students are expected to learn the concepts and lexicon of photosynthesis—and other scientific subjects—simultaneously.

But according to a recent study by Bryan Brown, an assistant professor of education at Stanford, and Kihyun Ryoo, a doctoral candidate in Stanford’s School of Education, students who learned the basic concepts of photosynthesis in “everyday English” before learning the scientific terms for the phenomenon fared much better on tests than students taught the traditional way.

The traditional approach

To help students master scientific lingo, teachers usually build word walls—interactive displays of the lingo, with graphics illustrating their links to photosynthesis. They hand out vocabulary lists. They use flash cards. They ask students to make up their own definitions.

But Brown and Ryoo say those techniques do not take into account that children learn new words as those words become valuable and meaningful to their lives.

“In contrast to foreign language instruction, where students are learning new ways to express familiar ideas, science instruction often involves the presentation of new ideas expressed through new language,” they write.

This is somewhat related to my old colleague Modesto Tamez’ attitude that vocabulary should be introduced at the end of a lesson, not the beginning (as is traditional). We often present vocab at the beginning of a lesson so we’ve got a common set of vocabulary for talking about a subject. But the result is that students tend to see science as the mastering of a bunch of vocabulary words — here are the words, now I’ll tell you what they mean, and that’s the lesson. Rather, we want students to experience the phenomenon, be intrigued, and then be given the words to talk about what they’re seeing. This is covered in one of my Science Teaching Tips podcasts where Modesto talks about this idea, in an episode called “When Words Fail You.”

Oh dear, do I have to rescind my “sciencegeekgirl” moniker? Twisted Physics just posted about a “Test your Science Savvy” quiz that was posted on World’s Fair. I got two wrong on that quiz (which disqualifies me from being a geek, by their scoring), but it was because I was thinking too hard, in a way. Like another reader, I thought that the statement “It is the father’s gene that decides whether the baby is a boy or a girl” was trying to trip me up about the difference between a gene and a chromosome. And I thought that the current theory didn’t see the Big Bang as an explosion per se (Jennifer O. certainly knows more about this than I do), but as “inflation” (which isn’t really an explosion).

So, in a way I scored poorly (only 9 out of 11) because I was thinking too hard… (“You will receive a lovely chemistry set as a parting gift” they tell me), which highlights the point of Jennifer’s post. She says:

Memorizing a bunch of facts and being able to pass a true/false quiz consisting of 11 “questions” doesn’t mean you can think critically, or have any in-depth understanding whatsoever of how science actually works.

In ed-speak, this is the problem that many schools focus on the lower levels of Bloom’s Taxonomy, which attempts to categorize different types of understanding. From lower-level to upper-level, they are:

  • Knowledge (facts)
  • Comprehension (demonstrate understanding)
  • Application (Use it!)
  • Analysis (support generalizations)
  • Synthesis (put information together in a new way)
  • Evaluation (judge ideas)

You can imagine it’s much easier to create questions that test a student’s ability to recite, say, the base pairs in DNA than to demonstrate that they can analyze a complicated case in genetics. Try it. I have. It’s really hard. Here are some example questions at each level of Bloom’s Taxonomy.

In a similar vein, the Active Learning Blog recently posted ways to assess students in constructivist classrooms (eg., classrooms where they’re making sense of what they’re doing instead of memorizing facts). That kind of learning environment is definitely tough to test! (I’d be curious what effect teachers think the No Child Left Behind standardized testing has had on our tendency to teach flat facts!)

I agree with a commenter on Twisted Physics — you need to know the basic level fact stuff, the “vocabulary” as it were. It’s important in order to be well-versed in the subject content, to some degree. But you don’t need to know certain things, like the speed of sound, as Jennifer O. says. You do need to know that there is a speed of sound, and what it means. And how to apply it. And how to evaluate someone’s proposal to test the speed of sound. If you want to be a science guru anyway. Or, perhaps, a geek. Maybe I’ll earn my stripes someday.