April 27

 

Today’s class is devoted mostly to the Sinking and Floating unit, with additional time to take plant measurements and discuss LTRP questions and progress.

 

Sinking & Floating (need clay, tubs, water …):

 

          Tell students about potential quiz questions for the unit re: floating/sinking fruit, floating/sinking soda pop cans [YouTube video with floating/sinking orange: http://www.youtube.com/watch?v=J8aReMgjMto].

·         Get a piece of clay to float. Keep track of shapes that did and didn’t float well. Get clay to float while holding load=its weight. Look for patterns differentiating the two groups.

 

 

 

 

 

April 22

[note: cancelled Monday’s class because of NARST]

Oil spill activity (need pans, water, colored oil, string, cotton, paper towel, detergent, wax paper, spoons):
Predict what will happen when the oil is added to the water?
What actually happened?
Use the string as a “boom” to contain the oil, then a spoon to try to remove the oil from the water. Does it work? What happened?
Use the cotton ball to remove the oil from the water. Does it work? What happened?
Use the paper towel to remove the oil from the water. Does it work? What happened?
Use wax paper to remove the oil from the water. Does it work? What happened?
Predict what will happen when liquid detergent is added to the oil and water mixture?
What actually happened when the detergent was added?
What problems did you have with each material?
How do you think these clean-up methods would work in rough seas? Cold weather? Near a beach? (opt.: Experiment to find out.)
Why do you think oil always floats on top of the water?

Students should collect plant data and water plants … Need to think through how to share data and keep it as objective as possible. I’m suggesting students measure plant height by measuring stretched stem height, based on what folks said before.

Discuss LTRP progress? Due in ~2 weeks …

OPT: Howard article on oil spill activity.

April 13

Cat’s Meow & Operational Questions: Have students try the demo/activity. … Ask students about things they could change in their experiments … List … (way to get students thinking about the properties of the materials involved) … write operational question for each of the following categories: substitution, increasing/decreasing, elimination … pick question you like best, id all variables that must be held constant … carry out experiments … Be sure to define operational questions: questions that can be answered directly by investigation (refer students to coursepack readings)
Have students try various experiments of their own to better understand the behavior they observed. Ultimately, lesson should contrast operational questions from those that are not directly investigable. Direct students to Shiland article in course pack.
Stress also how continued curiosity leads from one question to another, generally basing the new question on the results of the first investigation.

Discuss LTRP & Generate Questions: Assignment is due three weeks from today, so if you haven’t started already then you are limited to projects that can be completed in three weeks. This is fine, in most cases. It is time, though, to start thinking seriously about the assignment; it counts for 25% of the course’s grade. … On Wed. or next Monday we can talk about using online databases as an alternative way of doing the project. … Help students to understand that good Q’s usually involve investigating potential relationships between variables, testing predictions from explanations. A simple preference survey doesn’t fit well. Examples from the past (posted on the web):
• How much aspartame does it take before people can distinguish ‘regular’ from diet sodas?
• How does lack of sleep affect your ability to work math problems?
• Does quantity of alcohol served affect the size of my tip?
• Do expensive clothes stores carry a different range of sizes than discount stores? [not as good: What range of sizes do clothing stores carry?]
• How does location affect prices at nail shops?
• How do bird feeder locations affect food consumption?
• Does frequency of hand-washing decrease # of colds in an elementary classroom?
• Does having a snack help children perform better on math quizzes?
If time permits, students can discuss Q’s they’ve already thought of, or brainstorm other Q’s that could be investigated.

FOR NEXT TIME: Finish Swanson chapter, and have thought of at least one question that could be investigated for LTRP.

Apr. 8

Answer questions. Finish check activity (started Monday).

Discuss Carey chapter 1, go through one or two exercises …

Sampling Activities:
To start, help students distinguish between a sample and a population. Provide some examples, use as an introduction to the concept of figuring out exactly what population is being sampled (give a survey to 100 people in the area outside the bookstore, measure 10 rays off Newport Beach, find magnesium ion concentration in 100 mL water from L. Superior) , and thinking critically about the extent to which a sample represents the desired population.

1st Sampling Activity: Give students a sample of beads. Have students randomly sample 10 beads from population, records results, put beads back into population, repeat 5X. Then have group count how many are present for a color—RED (15%). As a class, we=ll discuss the data that students created, accenting natural variations (i.e., different sample outcomes). By definition, no one will be exactly correct. This leads to an issue: how confident can you be that the data from your sample accurately represents the overall population, if there=s absolutely no way to check? [If sample data says 29% of the people floss regularly, how many people in the U.S. actually floss regularly? And how sure are you of that figure?]

2nd Sampling Activity: Give students a very large number of some item, e.g., candy sprinkles or beans…much too large a number for them to count every item in the population. Have students sample the population, generating a number representing some attribute (everyone in the class is looking for the same attribute for their sample). Then, ask the overarching question about the fraction of the total population possessing the sampled attribute. Compare data, noting variation (and comparing variation with this larger sample size to that generated with the smaller bead samples).

Use this as an introduction to sampling concepts:
$ As sample size grows, the variation in outcomes decreases
$ As sample size grows, chances increase of getting data that is very close to the ratio in the population.
$ Size of the population is relatively unimportant.
If data permits, show students how the interval containing only 50% of all possible sample outcomes [.50, or 50% confidence interval] is smaller … the more confident you need to be, the larger your interval gets … THIS POINT IS OFTEN CONFUSING; may want to wait to introduce it formally until later. [NEXT TIME: Jelly Blubbers]
[See also Rutledge, M.L. (2001). An activity to demonstrate the concept of sampling error for the introductory biology classroom. Bioscene 27 (1), 3-6. on-line at http://acube.org/volume_27/v27-1p3-6.pdf]

[On-line applet for sampling This is an interactive applet that lets you run sampling tests. You vary sample proportion, sample size, etc. http://www.rossmanchance.com/applets/]

Set up plants, part II … Decide on Q to investigate, how to measure plant growth, key variables to consider, how to share data … Probably begin on Monday and carry through to end of class. I’ll ask about results and their interpretation on final quiz.

For Monday: Swanson (pp. 17-32) … tell students about the book and how the chapter they’re reading is almost just a checklist.

Apr. 6

Did students release butterflies? …

Discuss plant experiment … What were Q’s students investigated, and what do they think the answer to their Q’s might be? … How do they know? … What can you do to show your data in the way that most clearly shows an answer to your question (noting that this may not necessarily—or probably—be the same thing as showing all your raw data)? … May end up using class time discussing how to work with the raw data, kind of graph that may result, etc. … Afterwards, also discuss things students learned about how to grow plants from seeds that would be helpful if they were to do a larger project. Make sure this discussion includes talking about the kind of data to take, accenting that we are talking about data that is as objective as possible.

Piaget assignment is due April 15th. Discuss how this assignment works, and show the Piaget videotape.

For Wednesday: Carey, chapt. 1 – key pts: sci. is about noticing things, and trying to explain them. The explanation is different than the observation. One does not become the other.

Check activity … begin

(Wed: sampling activities)

Mar. 25

Today was the last day students collect data from their plants. We will be discussing this more next class. Today’s class also included the last few consumer product testing presentations, and a demonstration of how to search the ERIC database (at the library). One of the article review assignments may (optionally) be completed via a fast ERIC search, as discussed in class.

Mar. 23

The bulk of today’s class was taken up with student presentations on their consumer product testing assignments.

Mar. 18

The bulk of today’s class was taken up with the Mystery Powders quiz.

Mar. 16

Continue with Mystery Powders … students should soon be making unknowns for one another, investigating properties when powders are mixed. Toward the end of class, depending on how things are going with the powders, we can take some time to discuss graphing (see last Wednesday’s lesson plan) and/or discuss issues connected with the consumer product testing assignment due a week from today.

 

FOR NEXT CLASS: Quiz, including a question about solving a mystery powder mixture, and a question about the kind of graph that would be generated when answering a specified question.

Mar. 11

Make sure to mention importance not only of controlling variables for cons. prod. testing, but also generating plenty of data for analysis.

 

Continue with Mystery Powders

 

If time permits, can discuss the type of graph that would go with various examples of long term research project questions.