Technology

Day 128: Wave Superposition & Molar Mass in Reactions

/ Marta R. Stoeckel / Leave a comment

I’m out today, so I’ll find out tomorrow how things actually went.

Physics: Wave Superposition

Students used a Direct Measurement Video to start exploring wave superposition. Since I’m not there to listen in on their conversations, I’m having them submit answers to some questions in Google Classroom so I can look over what my students are thinking before class on Wednesday.

Wave DMV

Chemistry: Molar Mass in Reactions

Students went back to the nuts, bolts, and washers to introduce the idea of stoichiometry. I made up a “reaction” using those three elements and provided a total mass available for one of the reactants. Students used the hardware as manipulatives to determine how much of the other reactants would be needed along with how much of the product would be produced. When I did this last tri, students tended to ignore the manipulatives, so I reworked some of the questions to try and emphasize how the physical nuts, bolts, and washers can be used to check an answer.

IMG_1599

Day 122: Springs & Balancing Equations

/ Marta R. Stoeckel / Leave a comment

Physics: Period of a Spring

Students designed experiments to determine the variables that impact the period of a spring. I was very pleased with how many students pulled up their notes and results from the pendulum lab, in spite of the fact that it was on the other side of a week-long break, to help with experimental design and make sense of their results. For next year, I want to look at getting some additional springs. A lot of groups wanted to find a way to test the impact of the spring constant, and I only have options with relatively extreme spring constants, which made it tricky to get meaningful data.

IMG_1761

Chemistry: Balancing Chemical Equations

Students used PhET’s Balancing Chemical Equations sim as an introduction to what it balancing means. Last tri, I had a lot of groups skip straight to the game and play using trial and error, missing out on most of the sense-making. This tri, I took a few minutes to talk with students about why I structured the activity the way I did and students took the sim’s introduction and the questions I’d written much more seriously. Next time around, I want to add some questions to get students to focus a bit more on the significance of the subscripts vs. the coefficients.

IMG_1760

Day 92: Parallel Circuit Patterns & Reaction Rates

/ Marta R. Stoeckel / Leave a comment

Physics: Parallel Circuit Patterns

Continuing with Kirchoff’s Laws, students went back to the PhET circuit construction kit to look for patterns in parallel circuits. I have a lot of fun listening to student conversations during this sequence. The patterns that lead to Kirchoff’s Laws are just subtle enough to lead to some great discussion (and emphatic debate), along with lots of moments where students think they’ve got it worked out, only to break their own pattern.

circuit sim

Chemistry: Reaction Rates

Students timed a reaction between copper chloride and hydrogen peroxide, then made various changes to speed up or slow down the reaction. Students were doing a nice job of connecting yesterday’s discussion about energy in chemical reactions  (aided by PhET’s reversible reactions sim) to explain why some of today’s changes impacted the reaction rate.

Day 90: Circuit Patterns & Disturbing Equilibrium

/ Marta R. Stoeckel / Leave a comment

Physics: Circuit Patterns

Today, students started working on a series of labs based on the circuit patterns activities from the PUM curriculum. Today, students built series circuits in PhET’s circuit construction kit, measured the current and potential difference at each element, and started looking for patterns in their results. When using the voltmeter, I was pleased by how many students went back to a lab we’d done moving the ground wire of the multimeter to help explain why some voltages were negative, along with what that negative voltage means. Tomorrow, we’ll pull out the power supplies and resistors to see if their patterns work in the real world.

Screen Shot 2016-02-01 at 3.12.16 PM

Chemistry: Disturbing Equilibrium

Students played with moving a reversible reaction out of equilibrium. After mixing Fe(NO3)3 and KSCN solutions in several different test tubes. Once the reaction was in equilibrium, they tried something different, such as changing the concentration or putting the test tube into a water bath, to and observed the results.

IMG_1620

Day 88: Ohm’s Law & Limiting Reactants

/ Marta R. Stoeckel / Leave a comment

Physics: Ohm’s Law

Students wrapped up using the PhET circuit construction kit to develop Ohm’s Law. Students were able to pretty easily reason out the formula based on their graphs. Looking back, I wish I’d had students put their experimental conditions and equations on the boards, as well. I usually try to keep the boards pretty simple since I have some big classes, but I think that information would have added a lot of value to the conversation in this case.

IMG_1610

Chemistry: Limiting Reactant Practice

Today, students did some limiting reactant problems where the given and desired information is in grams, rather than moles. I was really pleased at how easily most of them worked through the problems. A lot of my students were struggling to connect ideas between different days earlier in the trimester, so it was great to see how many readily pulled out earlier skills and problem solving strategies to help today. I also saw a big jump in the quality of the questions I’m getting from my students; one student in particular was really focusing on the why when she was talking to me, when in the past she seemed most interested in getting something to write down. I’ve been having a lot of conversations with this class about how learning works and sharing why I do things the way I do, and I’m hoping I can get students to continue with the things I saw today.

Day 87: Ohm’s Law & Limiting Reactants

/ Marta R. Stoeckel / Leave a comment

Physics: Ohm’s Law

Students used PhET’s circuit construction kit to do a short activity based on the PUM materials to help orient them to the sim, then started looking for a relationship between current and potential difference. I loved it when, during the orientation activity, several groups got curious about the mysterious resistors in the kit, and immediately tried adding them to a circuit to see what they do, without any prompting or intervention on my part. There was also some great discussion and debate in one class about what exactly the blue dots represent. There were also many attempts to electrocute the dog.

dog circuit

Chemistry: Limiting Reactants

After a short percent yield quiz, we had some class discussion to formalize what students found in yesterday’s PhET sim on limiting reactants. I picked some reactant quantities for one of the reactions in the simulation, then had students get into groups and try to predict what they would produce and what the leftovers would be. Before students went to their groups, we had some conversation about what I was looking for. I tried to emphasize that I wasn’t after right answers; instead, I wanted them to share different approaches so we could decide on some useful ways to think about this kind of problem. There was a nice mix of students who focused on the equation given for the reaction and students who sketched diagrams.

IMG_1609

Day 86: Intro to Circuits & Limiting Reactants

/ Marta R. Stoeckel / Leave a comment

Physics: Intro to Circuits

I gave each group a bag with a mix of various items and asked them to use those items to try and light up an LED. In the past, I’ve told students their task is to light up the bulb, but they should keep track of what doesn’t work. This year, I was more conscious of stating the goal was simply to document what does and does not work so we could look for patterns, and I was much happier with how the exploration went. This was also the first time I used LEDs for this lab, instead of miniature incandescent light bulbs, and I liked the opportunity to reinforce that current has a direction. As an added bonus, the LEDs I have required two AA batteries, which gave the students more options to try. We wrapped up by watching a short excerpt from from the Private Universe series of MIT and Harvard grads trying a similar task.

IMG_1608

Chemistry: Limiting Reactants

Students worked through PhET’s Reactants, Products, and Leftovers simulation to introduce the idea of limiting reactants. I found a lot of students were looking for confirmation that their answers were right, even when the simulation showed the answer. When I talk to many of them, it sounds like they’ve gotten into the habit of assuming they are wrong in school. I need to continue to work on building a culture where my students feel like their ideas have value and to work on strategies to help students analyze their answers, right or wrong.

IMG_1607

Day 78: Electric Field Lines & Energy in Reactions

/ Marta R. Stoeckel / Leave a comment

Physics: Electric Fields

Students built off what they can see in the PhET Charges & Fields to develop the idea of what electric field lines represent. Students mostly got into trouble when they  thought their answers were too obvious and tried to come up with something more complicated.

IMG_1587

Chemistry: Endothermic & Exothermic Reactions

To introduce endothermic and exothermic reactions, we broke the terms down and talked about other words with the “therm” root and what that says about what these new terms might mean. Students then did some reading about endothermic and exothermic reactions. While the textbook doesn’t emphasize the role of energy in these reactions, I tried to bring that out in the short discussion after the reading.

Day 76: Electric Fields & Interpreting Reactions

/ Marta R. Stoeckel / Leave a comment

Physics: Electric Fields

Students used PhET’s Charges and Fields sim to look at how the size of a charge and the distance from a charge impact the magnitude of an electric field. Tomorrow, we’ll get from their data to the equation for electric field strength and draw some parallels between electric fields and gravitational fields.

IMG_1582

Chemistry: Interpreting Reaction Equations

Students worked on using chemical equations to determine which of the five reaction types was happening. I was really pleased by the way students started to talk about what is actually happening in the reaction, rather than just talking about the abstractions represented in the equation.

Day 66: Bouncy Balls & Molar Mass

/ Marta R. Stoeckel / Leave a comment

Physics: Bouncy Ball Energy

Students worked on collecting data to determine whether a bouncy ball looses more energy while its in the air or when it hits the table. There are lots of different approaches, and groups spent the majority of their time trying to figure out what might be useful to measure, which lead to some great discussions. The most elegant approach I saw was a group that did some video analysis in Logger Pro and produced a position vs. time graph. They argued that since each bounce’s parabola is symmetrical, the bouncy ball must be at the same speed for a given height on that bounce, so the energy stays the same while its in the air. Then, they compared the steepness of the parabolas for each bounce to show that the energy changes after the bouncy ball impacts the table.bounce graph

Chemistry: Molar Mass

Students practiced using electronic balances and switching between mass and moles. One of their tasks was to determine how many atoms of chalk it took to write their name on a lab table. The best part of today, however, was the ways I saw my students starting to come together as a class. I saw a lot of students, including some with a reputation for typically checking out in school, having great conversations about the quiz I returned or the day’s assignment. A few students even took over the whiteboard at the front of the room and started adding to what I’d put up there as they tried to make sense  of their measurements. I’ve been having a lot of conversations with these students about what effective collaboration looks like, since many have not really experienced it, and its great to see those conversations translating into the actions of my students.

IMG_1529