Unit 3 - Constant Acceleration Particle Model (CAPM)

Ahhhh... let the fun begin!  Lots of really cool activities to help students fully grasp the difficult concept of acceleration.  After many years of trying to teach this concept by telling, I'm excited to try out the modeling method to help my students master this topic.  The motion of a dynamics car along an incline was studied with a motion sensor and logger pro.  Lots of different variations of motion were sampled (cart released from rest, car pushed up the incline, sensor at top, sensor at bottom) with different groups performing different activities and boarding the results.  Discussions and questioning followed.  We developed an operational definition for acceleration being the "slope of the velocity curve" on a velocity - time graph.  We learned a "up up down down" song to help our students understand directional nature of acceleration and velocity and finally showed how the typical kinematic equations (I call them the Fab 4) could be written directly from the graphical data obtained from an experiment in which the car's motion was sampled moving and accelerating down the ramp with the motion sensor starting after the car was in motion (so that we had a non-zero initial velocity and starting position).  I found this portion of the unit particularly satisfying as it allows the student an opportunity to see how these equations (a staple of basic kinematics) are "derived" from (or at least accurately model) motion that students created simply by having a car accelerate along a ramp.  Seems like it will help take away the mystery, though I'm not sure it will be that meaningful to all students.  I think students that either dislike math, or have trouble with it (or both) will not find it all that useful or insightful, but for the "traditional" physics student, I think it will be very useful.  We culminated this unit with another practicum whereby we attempted to hit a constant velocity car by rolling a ball down a ramp.  A recommendation I have for improving this practicum (something I will do in my class) is to make sure the angle of the ramp is fairly small so that there is a significant time interval for the rolling ball (providing less margin of error).  With a steep ramp, the ball will travel the ramp distance in less than 1 second and is fairly easy to hit a moving car.  Something  even better might be to have the ball travel down the ramp and then along a horizontal section of ground before colliding with the car.  This might be too challenging for general classes, but would definitely work with honors or AP classes.

Again, loved this unit and think there are lots of great ways to help students truly learn acceleration.  I plan on implementing every one of these activities and am excited to see how well it works!

Unit 2 - Constant Velocity Particle Model

Unit 2 focused on numerous methods to analyze, interpret and represent constant (or uniform) velocity.  The models explored were graphical, motion mapping, and equations, including "area under the curve" or "area bounded between the relationship curve and the horizontal axis" representing the displacement of the object.  We used constant velocity "buggy" cars and motion sensors connected to logger pro in order to obtain the graphical data, and then used logger pro to develop the equations that fit the curves.  From this we discovered that the slope of the position time graph represents the velocity of the obj
ect.  We culminated the unit with a "practicum" whereby we attempted to collide two different constant velocity cars at an "X" placed in the center of the room.  Though most groups were not successful (only 1 in 4 collided), it was decided that most failures were attributed to the "curvature" of the cars.

Similar to unit 1, I liked how this unit included relatively straight forward experiments that provided meaningful and useful graphical representations from which basic physics relationships are derived.  Questioning techniques helped bring forward the relationships that were developed by the students.

Unfortunately, I missed a day of this unit due to illness.  So, although I found the unit useful, I know there is quite a bit of material I missed which I'll need to review in the provided literature.

I can see real value in performing these activities in my own classroom.  Unfortunately, I have been having hardware (and software) issues with my "datastudio" equipment and will need to get it fixed in order to fully employ the modeling method.

Unit 1 - Overview

In unit 1, we spent time developing graphical relationships for various physical quantities.  For example, area of a circle compared to its diameter, how far a mass needed to be hung from a fulcrum to balance a baseball, etc.  In all, there were 8 different activities that were modeled.  We then documented our results on white boards and presented our findings to the group.  During the discussion period, Don modeled the questioning techniques we might use in our own classrooms.

I liked how the activities were fairly easy to complete but provided some key insights into proportional reasoning.  Don's method of leading the discussion and making sure we understood proportions was spot on. I've done a couple of these kinds of experiments in my own class, but not to the level of these 8 experiments.  Nor have I had students white board their results and we definitely have not had the discussions.

I plan on implementing these labs and the board meetings immediately at the beginning of the school year.  I can see great benefit in having students engaged not only in the gathering of data and interpreting of the results, but also providing ample opportunities for students to apply proportional reasoning in a variety of different contexts.

Modeling Workshop

Currently taking a modeling physics workshop through the MAISD.  Learning new methods to facilitate student learning at the conceptual level, focusing on proportional reasoning at this point.  Lots more to come...