LOOPS Motion Unit: Notes from classroom trials March 20, 2009
Fayerweather Street School
Paul Antonucci, Kimberle Koile
Scott Cytacki, Seong Kim

There were two classes of 7th graders, nine in the first class (three groups of two and one group of three), ten in the second (two groups of two, two groups of three). The experiment took place in a science classroom, equipped with four approximately 4' x 4' square lab benches arranged in a square configuration, with approximately 3' between them. The groups were assigned by the teacher based on where students were sitting in an anteroom. The students typically walked a distance of 1.5 meters along the edges of the benches, with at least one group in each class walking 2.5 meters because they had the room. (One of the train stations was set approximately 1.5 meters from the motion sensor.)

We had one 100 minute session with each of the classes, longer than their usual classes, so the students were a bit burned out toward the end. Also, due to other events going on at the school at the time, both classes started at least 10 minutes late. We did Activity 2 and Activity 4, with some groups starting Activity 3 because they got ahead of the other students. In later versions of the curriculum, we definitely need "early bird" activities for those groups finishing early. (See the note below about keeping the students synchronized.)

In the first class, we followed the curriculum as planned, but in the second class, we decided, based on what we'd seen in the first class, to explore in more depth the idea of negative positions to see if the students could understand the idea and whether the idea proved useful in discussing velocity.

Overall, the investigations worked well: The set up and "finding the origin" were quite successful, and the idea of having everyone make a "train trip" and then compare graphs worked very well. (To simulate a LOOPS POLL, we had the students compare graphs by turning their computer screens so that everyone could see all the graphs.) Plus, these comparisons led the students naturally in to the "matching graph" page. They all liked the matching graph activity. Probably a few more questions on the matching graphs page, focused on just reading the graphs would have been good (e.g., "What time did you start the return trip?"), because it's quite easy to have it turn into a game, with comparisons, scoring, etc. We asked those questions verbally in class to keep the students focused on the science rather than the game aspect; it makes sense to include the questions explicitly in the activities. It worked adequately to have a pre-existing graph to be matched, (rather than taking one from the class) but it would be desirable to compare that method to the proposed interactive way of determining with the class which graph to match.

In some cases, groups of three worked better than groups of two. In one of the groups of three in the second class, all three students walked and worked on the computer. In the group of three in the first class, one student did the walking, one did the typing on the computer, and one interacted with the other two, e.g., guiding the walker. The teacher commented that she was "shocked" that the three girls were working together at all, and more so that there were working so effectively. (The teacher commented that the girls were not particularly friendly toward each other and that the walker was rarely engaged, instead spending most of class time chatting with friends in the class.) One group of two in the first class finished well ahead of the other groups and went on to Activity 3, the position stories. The teacher commented that she was "shocked" that one of the members of that group was so engaged, as he usually "never got anything done" and "never said anything". He was extremely vocal and enthusiastic about the activities.
Summary suggestions:

1. The velocity activity might best be split into two; it's too much for one class. The first class could, for example, focus on moving and graph reading, the second class could focus more on calculation (of velocities from positions), but should also involve movement and data-taking. The students in our trial didn't have adequate time for all the calculations and needed more help/hints/scaffolding for the second set. (They had about 40 minutes for this.) Plus, in the calculations, there were problems in wording which led a few students to look at "overall time" and movements (that is, time for the whole "back and forth" trip ) rather than what we wanted, which was the time and amount of movement for each particular segment. An idea to help establish the connections of the velocity and position graphs is to have the students read values (of position change and time) from the position graphs, make the required division to get velocity, and then have their calculated values plotted on the velocity graph, (or on a new graph). In the second class, we simulated a LOOPS POLL by having the students write their calculated velocities on the whiteboard.

2. Position. In the second class, we explored the idea, in response to a student's question, of "what would happen if we kept going back after we get to position = 0". This was a wonderful opportunity to pursue this idea, and the class was really engaged by it, and it worked quite well. To pursue that idea explicitly in the activities, we would need to add a few more steps specifically on this idea - going beyond zero into the region of negative positions. We might want more time in that case - more than one class. Otherwise, leaving the activity as is makes a fine one-period activity.

3. Predictions. Making predictions totally confounded at least two groups of students in each class; the students sat and stared at the screen, having no idea what to do, and some of them felt quite uncomfortable. (This difficulty was also true of some of the 6th and 8th graders that tried previous versions of the material out with earlier.) Giving the students more time or hints did not seem to help. The delay brought on by the difficulty that many of the kids had with the prediction step makes it difficult to keep the groups together for the first few steps, which is an important and helpful thing, because then the demos and explanations of how the sensors work can be done simultaneously, involving discussion with all the students. We recommend that in the case of velocity, the prediction be abandoned. For position, the prediction may be OK if we give a specific time limit; the students seemed less stumped by that graph. Another possible concern with predictions is whether it lessens the dramatic quality when they get their data. An alternative approach would be to have the students play with the motion probe and graphs first, then make predictions. During this initial exploration the origin could be at the motion probe. After that play the students would be better equipped to draw a graph about the train scenario.

4. Relevance. We had a good discussion in the second class on the real-world uses of motion sensor technology: robot navigation, identifying tremors in patients, analyzing movements of sports players. We definitely should include introductory steps describing some of these applications. Perhaps these could be optional screens, or for the "early birds" Part of this relevance discussion for was also about learning goals for the activity. The activity does not start with a description of the learning goals of the activity. It instead starts with "we are going to focus on the train system". It could say something such as: in this activity "we are going to use the train system to learn about position and motion, and reading graphs".

5. UI. We observed how students used the various navigation options in the interface. Most students used both the hierarchical list of activities and steps on the left and the back-and-forth arrows on either side of the compass at the top. They didn't see the point of the compass, and when they were asked at the end of class to click on it, they recognized the red dots as the pages, but agreed that the dots weren't necessary at the top of the screen. They used the navigation aids in different ways: When moving between activities, they used the left navigation panel; when moving between steps, they used the back-and-forth arrows at the top. Several suggested that the arrows be moved to the upper right or lower right corners (which was actually our original design, not implemented for the run because of time constraints).

The students liked the dots at the bottom of the embedded sub-steps, commenting that it helped them know where they were. For the most part, they figured out the semantics of the color scheme, but thought it a bit too complicated. (We agreed wholeheartedly.) Finally, the laptops were equipped with a mouse, in addition to having a trackpad. Most students used both devices, mouse for drawing and quick selection of new activities; trackpad for navigating between steps.

6. Technology. In general the software worked well. In one case it appeared that the combination of a flaky network connection and a particular laptop caused the software to freeze. After moving the old laptop to a new network, the application was force quit, and then restarted so the student's data was saved to a server. A new laptop then was started using the original login, which gave the student access to almost all of the previous data. There are two questions here: Why did the network cause the software to freeze? How can the process of switching to a new computer be streamlined? There was also an issue with a graph that got into a state in which it couldn't be resized. Switching pages and returning to the graph page fixed this problem.

7. Graph as learning tool. The teacher commented that letting the students dynamically adjust the graph axes was a great learning moment. The situation arose when a group of students had accidentally scrolled their data off the screen, and another group wanted to know what the data looked like that was off their graph (as evidenced by a gap in the data). The teacher stepped in to ask guiding questions to help the students understand. Ordinarily, an exercise such as the graphing one is preceded by an explanation of how to manipulate the graphs. We didn't have time to give this explanation, plus we wanted to see if the students discovered the graph manipulation functionality. We recommend that an activity be added that lets the students explicitly manipulate graphs prior to creating the train simulation graphs.