Feb. 25

Start first plant experiment. Students will be given seeds, cups, dirt, etc. and asked to come up with a question to investigate at their table. They will spend a couple weeks collecting data—so they should leave space in their lab notebooks, but the expt. is mostly preparation for a later experiment. So, as they prep and carry out their investigation, they should pay extra attention to variables they’d want to be paying attention to should they repeat a similar experiment. This investigation can be thought of as a pilot study for a later, larger experiment. … Take some class time to think about questions that could be investigated, variables that would need to be controlled for a fair test (introduce the technical terms), and what kind of data to record to address the investigation’s question.

 

Discuss article by Marsa … key terms: “randomized double blind experiment” and “epidemiological research” (or retrospective study) … Make sure students understand what the terms mean. Go on to discuss how one would study whether beta carotene prevents a type of cancer, a question mentioned in the article. (You would look at a group of people who had the cancer and a matched group who did not and compare how much beta carotene they ate.) How would one judge whether the investigation was trustworthy or not? (By examining how similar, or well matched, the two groups were that were compared)  … Author makes a key point: “Just because there’s an association doesn’t mean there’s a direct cause and effect link.”

 

Here’s something to practice with (Q: Is living near a highway bad for your health? If the family lives near a highway, are they more likely to give birth early to low birth weight babies? … What would a randomized experiment to investigate this question look like? … Clearly unethical, what would epidemiological research, or a retrospective investigation, look like? … How could you tell if this was a high quality study?) :

Highway proximity linked to birth weight

A Canadian study suggests that mothers living near highways are more likely to give birth to preterm or low-birth-weight babies. But contrary to previous studies, it found the association only in wealthy neighborhoods.

The study, published in the August edition of the Journal of Epidemiology and Community Health, looked at 99,819 births. They found that compared with living in a wealthy neighborhood farther away, living in a wealthy neighborhood within 220 yards of a highway was associated with a 58 percent increased risk of preterm birth. [STOP HERE FOR DISCUSSION]

“Low-income mothers are exposed to more risk factors,” said Dr. Melissa Genereux, the lead author and a resident physician at the University of Montreal. “More-advantaged mothers are protected from these risk factors, so they might be more affected by the addition of a single new risk factor.”

Feb. 23

Today we looked at a tape of Joanne DeMaria teaching Batteries and Bulbs, and students took a quiz.

Feb. 18

• Tell students about FOSS
• Teacher to Teacher tape….show section with Joanne DeMaria, students working on mystery boxes
• Tell students about voltage and current … introduce misconceptions … remind students about their original diagrams, discuss why they might think as they did

 

Discuss Marsa and other course pack readings; introduce/review concepts behind retrospective style investigations … Example from today’s paper—article discussing a study concluding that bicycling does not prevent bone loss. How could this be studied?

 

Discuss electromagnet investigations

 

Make sure students understand what might be on Monday’s quiz

 

Prep for Consumer Product Testing assignment with paper towel testing…. Use as group activity to illustrate the kinds of things looked for in the consumer product testing paper. With 2-3 brands of towels available, have students find which towel is more absorbent. Compare data from group to group. Discuss issues of repeated trials, controlled variables, and study limitations. [Have a copy of the assignment’s directions handy.]

Feb. 16

Class today includes a small lecture on fuses–what they are, how they work–and students then making one more complex circuit. 

 

Show students FOSS Magnetism and Electricity box. Tell them a bit about FOSS and the kits, then have students do an activity or two from this particular unit. Suggestion: Make an electromagnet that will pick up paperclips, or move a compass. What relationship, if any, is there between the number of winds of wire around the electromagnet’s core and the number of paper clips the electromagnet will pick up? (Hints: display results graphically, think about factors that need to be kept the same for the experiment to be “fair”)

 

FOR NEXT TIME: Marsa (…we’ll discuss this and other articles soon, prob. on Wednesday…quiz prob. next Monday)

Feb. 11

Feb. 11

Class will end today at 10:30 with the Emergency Evacuation Drill.

• Prediction Sheet #2
• Have students make more complex circuits—combinations of series and parallel circuits
• Students who are ready can be introduced to switches, concepts behind a fuse, using schematic diagrams, and/or making quiz cards.

FOR NEXT TIME: Rosenberg

Feb. 9

Batteries & Bulbs:

• Light bulbs with battery, bulb, and wire. Find other ways to do so. Figure out rules for lighting a bulb.
• Prediction Sheet #1
• Brief lecture introducing concepts of circuits.
• Go on to ask students to figure out how to light two bulbs so that they can remove one bulb and the other will stay lit. Demo battery and bulb holders.
• Introduce concepts like electrical circuit, short circuit, series circuit, parallel circuit.
• Introduce misconceptions…remind students about their original diagrams, discuss why they might think as they did, tell students about other common electricity misconceptions(?)—see Steppan’ book

 

Tell students about Science Times (for article due on Wednesday). … 

 

FOR NEXT TIME: Article 1 due

Feb. 4

Discuss readings

• Keys (“Inquiring Minds Want to Know”): Brainstorm at your table a short list of questions that a 401 student could investigate. Share.
• How do convergent (or cookbook) activities differ from divergent (open-ended, inquiry-based) activities? … Write a brief paragraph in lab book. Discuss at table, change what you wrote if you like, call on random student …
• Tell students about activities in this course, reiterate why they read these articles at this point in the course
• Remention the concrete/visible vs. abstract/intangible distinction.

 

Discuss graphs

Ask re: difficulties students might have had in using Excel; offer to meet with students outside class. Go on from there to discuss characteristics of good graphs (large, axes clearly labeled with name and units, linear axes, descriptive title—a question always works, points easy to see … generally a scatter plot or bar graph, smooth curves—not connect the dots …

 

Work with manatee data

For over 15 yrs the Florida Marine Patrol kept track of how many manatees were killed in the area they patrolled near Tallahassee. Some folks suggest that the increasing numbers of manatee deaths may be due to more and more people with powerboats sharing the same waters as the manatees. If I tell you that data about how many powerboats were registered in the same area is also available (for the 15+ year period), how might you go about investigating whether there really is a relationship? … What would you expect to find? How could you use a graph to see whether data supports the conclusion that powerboat registration and manatee deaths are linked? … THEN, show students actual data, ask them to make a graph investigating whether data supports the conclusion. Put graph in lab book. [Discuss: Does the data prove powerboats are killing manatees? Does the data support the conclusion? Does the data support any other conclusions?]

 

Discuss an article and its analysis

Study links TV and depression

The amount of time teenagers watch television increases their risk of becoming depressed as adults, researchers find.

You may be depressed by the amount of time your teenage couch potato spends in front of the TV, but according to a new study, all that television could increase his or her risk of becoming depressed as an adult.

Researchers at the University of Pittsburgh and Harvard Medical School looked at the media habits of 4,142 healthy adolescents and calculated that each additional hour of TV watched per day boosted the odds of becoming depressed by 8%.

 

Other forms of media, such as playing computer games and watching videos, didn’t affect the risk of depression, according to the study published today in the Archives of General Psychology.

 

Article does go on to point out that kids likely to become depressed may watch a lot of TV … correlation not cause

 

ALSO: Can discuss how to do a study examining whether kidney donors have shortened lifespans. … Accent “fairness”

 

Discuss autobiography assignment

 

FOR NEXT WEEK: Article 1 due a week from today … Tell students what the assignment is about.

Feb. 2

Show students (again) how to set up notebook. Be sure to leave a page for Table of Contents, fill in TOC as you go, and number pages for easy reference.

 

Begin today’s pendulum activities by having students make pendulums that swing at different frequencies and then hang them at the front of the room. Use this as an example of a way to make a graph into something more tangible and concrete. …

 

Next, students can look at the graphs that their classmates made. Compare graphs with length on the x-axis and those with frequency on the x-axis. For what kinds of uses would one be better than the other? … Also, have students look for features they notice that make the graphs more user friendly, i.e., easier to read and understand. … Collect student responses and thoughts, use this as a lead in to discuss how this course will define “good” graphs:

* large,

* axes clearly labeled with name and units,

* linear axes, usually starting at 0,

* descriptive title—a question always works,

* points easy to see …

* generally a scatter plot or bar graph,

* smooth curves—not connect the dots …

 

As a homework assignment, for next class, have students make a graph with group data to see how length affects a pendulum’s frequency (swings/min or swings/sec). Put length on the x-axis. Use class data. (So, make sure time is used for everyone to enter their data into a spreadsheet…) [Do you think it will matter whether your x-axis is swings/min or swings/sec?]

 

Graphing directions online at: www.csulb.edu/~acolburn/SCED401/GraphingDataWithExcel.htm. (Note that studs should follow directions for graphing continuous variables, part I.) … If computer and projector available, show students how to make graph with Excel. Use data other than that from pendulum for sample.

 

Depending on time, students can investigate whether a pendulum’s frequency varies with the size of the arc it swings through. Handout protractors. … Results can be used to make predictions about hand motion and frequency.

 

Depending on time, this might be a good place to begin discussing studies. Last week there was an article in the L.A. Times discussing kidney donors, and a study which said donors have lifespans that are the same as non-donors. Suppose you had a huge database with information about people at the time of their deaths, including whether they donated a kidney. What might you do with this info to set up a fair test of the question “Does kidney donation change lifespan?” … When you were finished, if you wanted to show people the results of your study, how would you do this?

 

FOR NEXT CLASS: Science autobiography is due. Bring it printed out. … We’ll discuss the three articles, too.