AY 300 Fall 09: Fourth day plan

• Everyone should have had at least one section by now so ask any or all of the following:
  • How did section go?
  • What did you do?
  • What didn't work?
  • What would you have changed?
  • Any cool/interesting/sad stories?
• Get most people to speak briefly on one of the above questions.

• For each reading, break into groups of 2-3 and discuss some questions. Present to whole class
• Reading 1: Discuss people's reactions to the Cross essay:
  • Are you convinced that collaborative learning is always superior to lecture learning? What are some pros and cons of group/peer learning?
  • Discuss the essay from a scientific paper standpoint.
    • Are they convincing?
    • Do they use real-world data?
    • Do they explain their experimental setup?
    • Do they refer to any possible errors in the data collection or presentation?
    • How general/representative is the data/students used in the study?
    • What kinds of further evidence would you like to see about the efficacy of collaborative learning?
  • Do any of the guidelines in the second portion of the required reading seem especially appropriate or especially inappropriate to your section(s)?
  • Do the claims in this article jibe with your experience leading section so far? To flip it around, would the author consider our group activities (section worksheets, demos, TALC, etc.) as 'effective'?
• Mention that this reading was certainly on the more philosophical end of the pedagogy spectrum and most of what we'll read will be more concrete/scientific and less theoretical (but we will return to some teaching/learning theory stuff later).

• Reading 2: Take volunteers from the audience for each way to discourage learning and:
  • Summarize it.
  • How/why does it discourage learning?
  • Is there ever a reason to purposely do it?
  • What are some ways to avoid it?
• What are some concrete pieces of advice you have taken/can take from this article?

• Choose a few students randomly to give a mock lecture:
  • One at a time, have a chosen student come to the board.
  • Explain for 3-4 minutes a concept of their choice as if doing a quick lecture review for an AY 10 section (e.g. a weekly recap).
  • The audience, acting as an AY 10 section, might ask a question or two during the lecture. Keep to a question or two (at most) per person.
  • Get a few comments/suggestions from the audience and instructors on their lecture style.
  • Include a problem, as mentioned last time, for some of the mock lecturers.

• Demo basics:
  • Demos are a great addition to a standard/dry worksheet.
  • Sometimes they actually do help elucidate concepts and students like doing “hands-on” experiments (this is a science class!).
  • As always, the EBRB is a great resource and has a page devoted to demos.
  • In addition, on a given topic's page in the EBRB, there should be listed any relevant demos.

• What makes a good demo?
  • Illustrating difficult physical concept(s)
  • Interactive: students can participate
  • A springboard to new topics
  • Straightforward: minimal risk of failure
  • Demo actually illustrates concept in question

• When demos go wrong:
  • Demos can and sometimes do FAIL!
  • Sometimes, especially in astronomy, they can confuse students more than help them or oversimplify a concept.
  • Materials may be missing or broken, so CHECK IN ADVANCE!

• Some of our favorite demos:
  • Describe them briefly
  • Remind everyone that most are written up in the EBRB and on the Resources handout (and wiki page)
  • Do bolded ones?
  • Keep going until a couple minutes before this chunk of class is supposed to be done
  1. Arc lamps: Put high voltage through tubes of gas and look through diffraction gratings to see spectral lines. On the EBRB Light Blackbodies Spectral Lines and the Doppler Effect page, “under Line spectroscopy and arc lamp activities”.
     • C10 already did this, this year.. Check if useful to describe for 10…?
     • Head GSIs will train GSIs
     • Students like this one
     • Make sure the stuff is there if your section is early in the day.
     • Test it yourself and make sure you can see lines so you can help your students better.
  2. Warping of Spacetime: A 2D analogy using stretchy black fabric and balls/weights. No worksheets exist in the EBRB for this one, but feel free to make one! We might do this one in Ay 300 later in the semester.
  3. Celestial sphere, phases of the moon, seasons, orbits: Styrofoam balls, a lamp or flashlight, people getting up and moving around. Many worksheets go with these kinds of demos and can be found on the Demos page of the EBRB or on the Celestial Sphere, Gravity and Orbits, and Earth/Moon/Sun System pages of the EBRB.
     1. Retrograde motion (Discuss pitfalls)
     2. Day & night on Earth (circle up around a lamp and groups of 3)
     3. Lunar phases (balls on a sticks around a lamp and groups of 3)
     4. Seasons (circle up around a lamp)
     5. Lunar rotation and orbit (i.e. tidal locking) (one person orbits another with the Moon's arms outstretched)
  4. Parallax with your finger (very simple, “close one eye then the other” kind of thing)
  5. Doppler shift of sound (whirling a buzzer on a string)
  6. Class H-R diagram (too long to do in Ay 300)
  7. Stating in words, stating in math, drawing, and acting out Kepler's and/or Newton's Laws (can be done with a worksheet, or just have students take notes as each group presents their law) (too long to do in Ay 300)
  8. Donut/bagel on a string (though I'm sure profs will do it in class)
  9. Jumping on a chair with balls being thrown (though I'm sure profs will do it in class)
  10. (Rayleigh) Scattering of Light: Fill a fish tank with water and a couple drops of milk and shine a flashlight through it to show scattering of blue light and transmission of red light. On the EBRB Light Blackbodies Spectral Lines and the Doppler Effect page there's a worksheet called “Emission, Absorption, Scattering, and Nebulae” and one called “Scattering Demo.”
  11. Planetary Nebulae (and Limb Brightening and Optical Depth): use a Hoberman sphere covered in Christmas lights to show how spherical radiating clouds can appear ring-like. On the EBRB's Stellar Evolution page, there's a worksheet called 'Limb Brightening: “Hoberman Planetary Nebula” Demo.'
  • Physics has some, but it's kind of a pain to check them out, but some are good for section and some are good for full lecture.
• Remind everyone that they're required to “Design a Demo”:
  • You are required to design a demo for the class you are teaching.
  • Hopefully the demo will be easy to construct so that we can get funds through Dexter for you to build the demonstration. If the demo is very expensive, you will only be required to write-up your idea for the EBRB so that the idea can be revisited later by future GSIs.
  • Will discuss more later in the semester

• We'll pass out a handout in a few minutes which summarizes pretty much all the points we're about to make.
• These points are valid for both quizzes and exams:
  • Test the material emphasized - Exams should reflect the fact that students should know the big concepts really well, as opposed to knowing a bunch of smaller concepts only peripherally.
  • Keep questions short and to the point - Students should spend the majority of their test time thinking and answering/writing, NOT reading.
  • Edit questions for clarity - Clear questions tend to be shorter and if anything is ambiguous it confuses and slows down students and makes it harder for you to grade it fairly. Have someone else take your exam to give some feedback. If you're taking an exam for someone else, be critical and think about possible ambiguities.
  • Don't write a long test - Keep it concise, to the point, and clear! The rule of thumb is your average student will take double or triple the time it takes a GSI to complete the exam. Also, 90% of your students should finish the exam completely in the allotted time.
• Quizzes vs. Homeworks
  • They're quite similar in their construction and type of questions.
  • The main difference is that quizzes should be shorter and have easier questions, since students have much less time to work on quizzes and must work on them alone.
• Quizzes are:
  • short
  • usually given in section
  • questions are of exam difficulty (i.e. easier than homework questions)
  • Not too in-depth or calculation-based. Some light calculation might be OK, but take care. (Not everyone will remember a calculator no matter how many times you remind them, and many people will be petrified of the idea of computing things on their own.)
  • usually only cover recent material (i.e. the past 2-3 weeks)
• Quizzes are used:
  • by the GSI to gauge each students' understanding of recent material individually (as opposed to homeworks which can be done in groups)
  • by the student to gauge their own understanding of recent material and get a feel for what a college level intro science course non-Scantron exam will look like and what level of understanding they are expected to have for the exams
  • by the prof to get a grade early in the semester that's more important than a single homework, but isn't the big production that an exam is (you might not have covered enough material for a full exam)
• What makes good ones?
  • not too long (both in length of individual questions and number of questions)
  • not too hard
  • not too easy (shoot for a variety of difficulties in questions)
  • relevant to recent material
  • varied in the types of questions (multiple choice, fill in the blank, calculation/mathematical, read a graph, free/paragraph response)
  • unambiguous with easy-to-read questions
  • not mathematically demanding - questions should probably not require a calculator and should definitely not include extensive tedious calculations
  • representative of same knowledge required for exams
  • gradable for partial credit (not simply binary right/wrong like Scantron exams)
  • specific about what you're looking for in free response type questions: Don't give students the opportunity to 'core-dump' for a problem, it wastes their time spewing forth useless information and makes your life tougher when you have to grade the mess.
  • quick to grade (this makes your life much easier and helps the grading be more fair for all of your students)
• Quizzes are meant to be relatively low stress (especially compared to full exams)
• Distribute the anonymized quiz questions
• Break into groups of 2-3 and critique the questions
• Come back together as a class and discuss a question or two from each group
• Hand out the handout.
• We will discuss grading these quizzes next week

• Next week, we will discuss how to write good exam questions. In preparation, write at least one multiple choice exam question and at least one free response exam question, using your best efforts. Feel free to be creative! The questions should be targeted for the Ay 10 level and can cover any topic in astronomy or relevant physics. We will anonymously critique each other's example questions in class next time.

• An optional reading that's relevant to the writing assignment is in Learner-Centered Astronomy Teaching: Strategies for Teaching Astro 101 (aka the Orange Book) by Slater & Adams. (There's a copy of this book in the seventh floor Astronomy Library in the bookshelf to the right of the door as you walk in. The book is thin and its spine is orange. Also, both Peter and Jeff have copies that you can borrow for a day or two – as do a few other astro grads.) Again, reading the following chapters may be interesting but is not required:
  • Chapter 7: Strategies for Writing Effective Multiple-Choice Test Items
  • Chapter 8: Alternatives to Multiple-Choice Tests (especially pages 71-77, 82-84)

As always, spend a few minutes exchanging ideas for what to do for your next section.