Pendulums

Pre-Assessment

1. What is your personal experience with swinging on anything like a trapeze?
swinging on a swing
swinging on a trapeze bar (on kid's playlets) by your knees
swinging on a rope out over a lake/river

2. What applications to "real life" do swinging objects have?
pendulums on clocks, metronomes
swings

3. What is your prediction about what will happen if 2 people are on one trapeze and only 1 is on the other and the second switches to the one?
The one who "gave away" a person will lose momentum? The new group of 2 will have more weight and swing "harder." ????

4. What understanding or ideas do you have about the science of back-and-forth swinging objects?
kinetic energy is the energy of movement
potential energy is the ...potential (the lull before it swings back)
potential energy= mass*gravity*height?

Predictions

I think lower weight will swing more times in 10 seconds than higher weight.
I think doubling the weight will half the frequency, but double the total length of time that the pendulum keeps swinging (if we didn't stop it after 10 seconds).

Experiment

COntrol: Length (15 cm), angle of starting swing (22.5 degrees), time (10 seconds)
Variable: # of Washers

1 washer: avg. of 12.25 swings
2 washers: avg. of 12.375 swings
3 washers: avg. of 12.25 swings
4 washers: avg. of 12.25 swings

Conclusion: Weight does not affect frequency of pendulum swings

Our Experiment

Control: Angle of starting swing (22.5 degrees), Time (10 seconds), No. of Washers (4)
Variable: Length of String

20 cm: avg. of 10.625 swings
25 cm: avg. of 10 swings

Conclusion: We predict that the longer the string, the fewer number of pendulum swings per 10 seconds. --> An inverse relationship to pendulum length and frequency of swing.

BBW Lesson Plan

Learning Goal: Electricity requires a complete circuit for the current to flow.

Learning Performance: Students successfully light a lightbulb and communicate why it works (orally, written, pictorial)

NSES
Physical Science
Content Standard B: Light, Heat, Electricity, & Magnetism
Benchmark: Electrical circuits require a complete loop through which an electrical current can pass.

Activity:

Give students flashlights to take apart and explore. (Rearrange parts, identify sequence, just play)

Ask students what makes the light bulb in the flashlight work?
(Write and draw findings is Science Notebook.)


Give students batteries, bulbs, wires (already stripped for younger children) and ask them to see if they can light the bulb from what they learned with the flashlight. (1 bulb, 1 battery, 1-2 wires) If (when) students are struggling, give them bulb holders to screw the light bulb into. Make sure they know it does work without the bulb holder. (Some students will be determined to do it without, and that is okay. The bulb holder just helps with fine motor abilities.)


As students are successful, take a break and ask students to tell you how to (or have students) draw their construction on the board. Battery-wire-bulb-(wire)-battery.


Point out that in order for the light bulb to light with a battery or with a flash light, we need to have a continuous pathway, circuit. Introduce electric current.

Ask students to evaluate if they have been good scientists. Did they look at evidence? Ask them what their evidence was. (Trial and error.) Was this a good experiment? Why? Write in Science Notebooks.

Next Day

Ask students to guess/explore where the full circuit is in a flashlight.
(Write & draw in Science Notebook.)
With help or alone, students need to figure out and see visual/physical representation that the flashlight creates a full circuit also.


Ask students how they think the inside of a flashlight must look.
Draw on the board what they have so far (simple circuit), and guide students in figuring out the inside of a lightbulb.

(Further lesson on what is inside batteries by experimenting with different fruit, vegetables, and other objects to light a lightbulb.)

5 Essential Criteria	Example	Explain	Teacher- or Student-driven?
Engage	Teacher asks what makes the bulbs light up in a flashlight.	Scientifically relevant question	Teacher
Evidence	Students take apart flashlight and explore why it works. Try to recreate evidence with BBW.	Experience trial and error of what works	Student
Explain	Students record findings of a complete “circuit” by drawing diagrams or explaining the concept verbally	Making explanations based on results	Teacher (requires drawing or writing in Sci NB)
Evaluate	Teacher asks students to evaluate themselves as scientists and the validity of their experiment	Evaluating evidence and explanations	Teacher
Communicate	Write/draw conclusion of findings in Science Notebook	Upgrade spoken explanations to written &/or pictorial form.	Student (no specific questions to answer)

Moving Beyond the Science Kit: Explorations of Electricity & Atoms

I really liked this reading because it provided a clear non-example of inquiry juxtaposed* with an awesome example of guided inquiry! "Ms. Travis" still used the same BBW kit, plus some extra supplies, still arrived at the same vocabulary, and used inquiry-driven exploration of electricity. Even her classroom managment was better - her activities allowed for maximum participation whereas "Ms. Stone's" students were fidgety and bored because only a few students could use the materials at a time.

For the sake of practice, and because I really thought of this while I was reading: Did Ms. Travis's BBW unit really follow the 5 essential features of inquiry?
Engage in a science-oriented question: Yes, students were encouraged to explore how flashlights work, and then asked if they could light a bulb with one battery and one wire.
Priority to evidence: It's hard for me to tell, because trial and error is certainly a form of evidence, but they weren't using any outside resources. They did experiment with what worked and what didn't, so I think evidence was rather vital to the process. (Just not labeled as "evidence" or "data.")
Formulate explanations: Students determine that unscrewing a bulb or disconnecting a wire in a series circuit makes all the lights go out. They explain this by concluding that the pathway (circuit) must be broken.
Evaluate explanations: I don't think the students really evaluated their explanations. I guess evaluation happened, but in the form of the teacher confirming explanations as correct or incorrect.
Communicate & justify proposal. Students jumped to the next step (or the first step again) of inquiry - asking new questions. Did they orally communicate explanations when Ms. Travis helped them assign terminology to their new knowledge?

I would call this successfully meeting the 5 essential features of inquiry, but that's also because I think it looks like inquiry, and smells like inquiry and barks like inquiry. But true Inquiry is all or nothing with these 5. I am still trying to determine if I am being to lenient with the qualifications or if I am actually figuring out that inquiry can still be accomplished even if the teacher is providing some of the steps.

*I had to work it in sometime.