Needing to teach Newton’s Laws?  Don Rathjen, staff educator at the Exploratorium, has been teaching mechanics to students for over 20 years.  This one’s an old favorite — a noisy activity with wood flying everywhere.  You can listen to Don demonstrate how to teach the activity (and geekgirl has some fun with it too) on my Science Teaching Tips podcast.

Here’s a PDF of the activity, and the related Old Tablecloth Trick.

From the activity writeup:

The key concept here is inertia, or resistance to change in motion.  Mass is a measure
of inertia, as shown in Newton’s Second Law, F=ma; for a given force, the larger the
mass, the smaller the acceleration, or change in motion. The “whack” force applied to
the bottom block is far larger than the opposing friction forces from the table and
the remaining block stack, so the bottom cassette undergoes a large acceleration.
Because of the frictional force between the bottom block and block stack
above it, the stack accelerates as well; but the force is small and only occurs for a
very short period of time, and therefore doesn’t give the relatively massive stack much
acceleration before the bottom block is gone. So the stack just drops. Notice as the
blocks are knocked from the stack, the top stack moves farther. Since the stack has
less mass, it has less inertia.

More of Don’s activities here.

Hey, I just stumbled upon this very useful list of blogs from the National Science Digital Library — all having to do with education, digital technology, and inquiry, among other things. If you’re a STEM educator (that’s Science, Technology, Engineering & Math education, definitely check out this list. What a find!

Also check out the Top 100 Education Blogs… those are organized by topic,

College | E-Learning | Education News | Education Policy | Internet Culture | Learning | Library and Research | Specialty | Teaching | Technology

OK, sure, that’s a boring title for a post. But this list represents THE most accepted principles of how people learn. We all learn, even if we’re not in school, and knowing how you can learn better is very useful. And for teachers, this represents the distilled knowledge of how you can help your students. We are very interested in specific ideas of how to use any of these principles in practice in the classroom — that is the challenge!

This list comes from the Eberly Center for Teaching Excellence, ©2007, Eberly Center for Teaching Excellence, Carnegie Mellon,
PDF of this document, containing references

The following list presents the basic principles that underlie effective learning. These principles are
distilled from research from a variety of disciplines.

1. Prior knowledge can help or hinder learning. Prior knowledge is the lens through which we view
all new information. If that lens is inaccurate, incomplete, or naïve, it can interfere with or distort the
integration of incoming information (Clement, 1982; NRC, 2000). Consequently, it is important for us to
know and address the misconceptions students hold, and to connect new information to accurate
information they already possess.

2. Motivation generates, directs, and sustains learning behavior. Motivation influences the amount of
time and effort students devote to learning and supports their continued engagement when difficulties
arise. Motivation may be influenced by a number of factors, such as students’ interests, goals, and
expectations (Hidi and Renninger, 2004; Bandura, 1989; Carver and Scheier, 1990), students’ beliefs
about learning (Schommer, 1994, Dweck, 2002), and emotional experiences surrounding the learning
context. In addition, students learn best when the classroom environment provides a balance between
support and challenge (Kuh, 2005). Finally, knowledge itself can be a powerful motivator – the
more students know, the more they want to know.

3.The way students organize knowledge determines how they use it. Knowledge representations that
accurately reflect the concepts, the relationships among them and the contexts of use, enable students to
retrieve and apply knowledge both effectively and efficiently. Our knowledge representations in turn
shape further learning (diSessa, 1982; Holyoak, 1984; NCR, 2000). When knowledge is organized
according to superficial features, when the connections are inaccurate, or if the representation is a set of
disconnected and isolated concepts, students can fail to retrieve or appropriately apply their knowledge.
We need to help students learn to organize knowledge the way experts do, around core concepts or big
ideas that guide expert thinking about our domain, and we need to identify and correct students’
disconnected information and inaccurate links.

4. Meaningful engagement is necessary for deeper learning. Meaningful engagement, such as posing
and answering meaningful questions about concepts, making analogies, or attempting to apply the
concepts or theories to solve problems, leads to more elaborate, longer lasting, and stronger
representations of the knowledge (Craik and Lockhart, 1972). By forming more connections to related
ideas, these activities increase the likelihood that students will be able to retrieve and use the concepts and
skills when they are relevant.

5. Mastery involves developing component skills and knowledge, and synthesizing and applying
them appropriately.
Many activities that faculty believe require a single skill (for example, writing or
problem solving) actually involve a synthesis of many component skills Anderson et al. (1989). To
master these complex skills, students must practice and gain proficiency in the discrete component skills
(for writing this may involve identifying an argument, enlisting appropriate evidence, organizing
paragraphs, etc; for problem solving it may require defining the parameters of the problem, choosing
appropriate formulas, etc.) To perform complex tasks, students must also practice and gain proficiency in
synthesis, in other words organizing and integrating component skills into a coherent whole. Finally,
students must understand the conditions and contexts of application and must practice applying skills and
knowledge appropriately in new contexts, otherwise they may have difficulty transferring knowledge and
skills learned in one context or another (Singley, 1989).

6. Goal-directed practice and targeted feedback are critical to learning. Goal-directed practice
involves working toward a specific level of performance and continually monitoring performance relative
to clearly define goals. When these goals are explicitly communicated to students, they guide and support
students’ purposeful practice and help students monitor their progress. In addition, students’ practice is
more effective when instructors (a) provide feedback that explicitly relates students’ performance to the
criteria, (b) ensure that the feedback is timely, frequent, and constructive, and (c) provide opportunities
for them to incorporate that feedback into further practice. (NRC 2001; Wiggins 1998). Instructor
feedback can come via formal (e.g., quizzes, papers, exams) and informal (e.g., classroom activities)

7. Students must learn to monitor, evaluate and adjust their approaches to learning to become self-
directed learners.
In other words, students must become conscious of their thinking processes. This is
called metacognition (Matlin, 1989; Nelson, 1992). One way to do this is to require students to explicitly
monitor, evaluate, and reflect on their own performance, and provide them with feedback on these
processes. To help students develop these skills we can model the process for students, by showing them
how we approach problems, question our strategies, and monitor our performance. Alternatively, we can
provide a series of explicit prompts or questions that ask them to monitor and evaluate their performance.
With sufficient practice students should eventually internalize these processes and use them without the
need for external aids.

8. Students develop holistically and their learning is affected by the social and emotional aspects of
the classroom climate.
Students are not only intellectual but also social and emotional beings, and all
these dimensions interact to impact learning and performance (Pascarella & Terenzini, 2005). The social
and emotional aspects of the classroom climate affect some students in ways that enhance or hinder
learning (Ford, 1992). For example, students will be more likely to take intellectual and creative risks if
they feel supported and respected. By the same token, when students fear ridicule or persecution, or feel
marginalized or stereotyped (Steele & Aronson, 1995; Walton & Cohen, 2007), they may disengage from
classroom participation and learning opportunities.

Hey, I’ve posted a new episode on my podcast.
Check it out; I think you’ll like it!

Title: Science Teaching Tips
Episode: Hands-on Science
When staff physicist Paul Doherty began to teach, he started by doing lots of demonstrations. But now, he explains, he has students get their hands on the science, which helps them to understand the calculations.
Paul Doherty’s Web site:


I’ve posted a new episode of my Science Teaching Tips podcast…

That’s a Good Question

TI staff biologist Karen Kalumuck tells us how she tries not to answer every question in the classroom -– instead, she guides her students to discover ideas for themselves.
Karen Kalumuck’s website:

cstaindex_02.jpg I just came back from the CA Science Teachers Association in Long Beach — a very good time. I like science teachers. They’re erstwhile, smart, and care about kids. I gave a presentation on electrostatics — you can download my handouts.

I saw one very good presentation on how to transform traditional cookbook-type labs to be more inquiry oriented and engage the kids. Check out his pretty pictures of dissolving M&M’s! I also liked his activity for showing radioactivity using M&M’s, and showing the probability wave around an atom using markers.

I’ve posted a new episode of my Science Teaching Tips podcast…

Episode: 18. Take it outside

Sometimes kids don’t have much experience with nature. TI teacher coach Kim Marie Hansen tells us how she got her inner city students outside and observing the world, by using nature journals.