## Day 130 – Conservation of Momentum

Physics 11 – We finally finished the video lab, after 2.5 days on it. Whew.  I’m afraid we don’t have much to show for it.  A few students had some insightful thoughts on what they observed but really it was too little for too much time spent. I blogged much more about it on my edblog.

One student was able to claim that it seems as though the momentum is transferring from one object to the other, which was a great thought. Another student reasoned that momentum should be conserved since Newton’s Third Law tells us that the forces are the same but in different direction, which means that whatever momentum one object gains, the other must lose.

## 122 – Direct Instruction on Momentum

Physics 11 – I’m becoming more aware of cognitive load issues in the classroom. This, coupled with my doubts in using the suggested paradigm lab from the AMTA Modeling Instruction resources, I decided to simply tell the students what momentum and impulse are, as well as give some worked examples.

## Day 104 – Energy Skateboard Park

Physics 11 – After a two year hiatus, I returned to the Phet Energy Skateboard Park. This was the student’s first exposure to energy bar charts, after having spent a class on discussing energy as storage systems, and representing energy storage in pie charts.

The handout in the picture above has some leading questions for the kids to use while exploring the simulation. They didn’t hand in the worksheet. Instead, I used some plicker questions to check their understanding.

## Day 92 – Barbie Bungee Jump

Math 8 – The Barbie Bungee Jump is a really nice activity that works in so many different settings in secondary school. I’ve used it in Math 10 for graphing linear relations/functions, I’ve used it in Physics 11 as a graphing warm-up and modeling example, and this year we’re using it in Math 8 for ratios and rates. In a few weeks we’ll come back to it, and tie it in with linear relations.

I’m working on this with my teacher candidate.  Below is the handout that she developed and I tweaked (but just a little bit).

Math 8 Barbie Bungee Jump

## Day 77 – Choices

Physics 11 – Some students have been coming for extra help.  There are two recurring themes with students in physics. Well, there are lots more but here are two.

1. Students are pretty good with graphical and diagramatic representions, but transferring those to actual equations is tricky for them, especially when dealing with symbols instead of numbers. I think many kids are on the threshold of formal reasoning.
2. Kids want to know how to get from A to B before they start solving a problem.  They’re not used to the idea of starting at A, trying something out, discovering something, and slowly working to B.

## Day 68 – Phrustrating Physics

Physics 11 – Today we had two main tasks. First, the students wrote a quiz with 4 different learning objectives: drawing force diagrams, determining if forces are balanced or unbalanced, knowing what vectors are, and Hooke’s Law. In general the quiz wasn’t done very well and since there were four learning objectives, class overall averages dropped by almost 5%. I think many students simply did not study.

We also finished the Fnet lab and analysis. I’m very fuzzy on whether it was worth it.  These videos are best used as secondary teaching tools, but I used it as the initial tool since we don’t have good (ie any) lab equipment for Fnet experiments. I really hope to get some probeware next spring so we can do labs like this hands-on. Doing this exact lab with probeware means that:

• lab software shows the x-t and v-t graphs instead of abstract numbers and calculations
• each group can ran multiply experiments with relatively quick data collection
time can be spent on analyzing and thinking, instead of calculations

## Day 66 – Fnet Direct Measurement Video

Physics 11 – Students analyzed a video which shows a fan cart accelerating on a low friction track. Through some data recording and calculations students were able to find the force of the fan and the acceleration of the cart.
I’m very unsure of the usefulness of this lab activity. The real goal of seeing and thinking about force and acceleration is likely being lost in calculations and figuring out what is going on with the video.  Stay tuned for next class…

## Day 54 – Whiteboarding Hooke’s Law

Physics 11 – Students presented their results on whiteboards today. In one class it is like pulling teeth to get students to talk in a whiteboard meeting. It is incredibly frustrating. I spoke with a few students after class, and they thought that maybe 1/2 the class was actually able to answer or question things that were said during the meeting, but chose not to.

Students did a good job of determining that the slope of the line on a Fs vs x graph is the stiffness of the spring, so that was pretty cool. Many groups didn’t think to find the equation of the line which was another beat my head against the wall moment. I really would like to get a modeling workshop here in Vancouver so I can improve on this aspect in my classes. Students are slowly coming around to the idea of modeling physics, but other details like having the kids take over discussions in class, along with timing on topics, continue to elude me.

## Day 8 – Buggy Whiteboarding

Physics 11 – Today was the students’ first shot at whiteboarding models that they’ve developed.  The photo above is interesting because during their presentation, this group realized that the direction on their graph was wrong.

The group below has a valuable statement on possible errors in data:

And the group below were the only ones that got to point of getting a mathematical model of the buggy motion. They had some good things to say with their presentation, more than what is shown here.

## Day 14 – Buggy Challenge

Physics 11 – Today the students had their first buggy challenge.  I asked them to use their graphs from their CV Buggy lab to develop a strategy for predicting where the fast and slow buggy will collide if they’re given a time.  A few groups got the idea right away, while some groups really wanted to calculate something. Overall the students came up with good, workable ideas.

After completing their challenge, students continued along with some modeling worksheets.