AY 300 - Fall 2013: Seventh Day Lesson Plan

Today's class will discuss how to run demos and create effective grading rubrics.

• Touch on how to effectively administer demos.
• Grading rubrics
• Teaching philosophy ideas?

Make sure that both people on either side of you are not GSI-ing the same class as you.

Section recap will happen only as a class today, since it's short.

Open the floor up for general questions and sharing about how sections are going. Some questions include:

• What did you do?
• How did you implement your activities?
• What worked?
• What didn't work?
• What would you do differently?
• How did you assess learning?
• Did you receive any unexpected questions/reactions/etc.?
• Did anything unexpected happen?
• What were you thinking about while you were running section? Any moments of panic?

(10 min) In groups of three, share your teaching philosophy (rotate through the philosophies). Share one aspect that you enjoyed to each member.

(10 min) The instructors will spend some time talking about how to effectively run demos and share some of the better demos that are available to them.

• 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:
  • 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.

• Activity in groups of 3. Each group receives the same free response question.
• Have each group develop a key and rubric for the question. (5 minutes)
• Give each group one student response to that question (three different responses, one for each group). Have each student grade the quiz based on that rubric individually. (5 minutes)
• Have students compare your grade with others in the group and discuss. (10 minutes)
• Discuss as a class and recap the main ideas of grading as a class. (10 min)
  • emphasize that reading some responses first is important.
  • discuss how to handle erroneous info.
  • The most important part of grading: Grade fairly and consistently for ALL students.
  • Try not to look at student names while grading anything.
  • Grade in blue or green. My (Aaron's) philosophy: Grade your own work in red, because you don't care about your own feelings. Grade other people's work in blue or green.
  • GRADE WHAT YOU TEACH AND TEACH WHAT YOU GRADE.

• Most questions should have 1 and only 1 correct answer (matching, fill in the blank, put in order, etc.).
• Paragraph or few sentence responses or plotting can be uglier.
• Try to give partial credit where you can. Always give points for correct steps even if the final answer's wrong. If they get the final answer but their steps or logic to get there is wrong, give them some points, but not too many.
• Obviously if they screw up part (a) by a factor of 2, but carry that extra factor through parts (b) through (f) and get everything else right (while including the factor of 2), they should only lose points on part (a). Also, stress this fact to your students so they don't get frustrated if they can't do (a), but the rest are doable (maybe even tell them to make up an answer to use for later parts, or in the question say 'use 5km for the rest of this question if you don't get part (a)').
• In longer answers, you should usually reward for correct information more than you punish for incorrect information. With that said, if they say something really wrong or even contradictory to the rest of their answer, they should be penalized a decent amount.
• Hopefully on your quizzes and exams you stress to students that they must write clearly and explain their steps and logic clearly. If you can't read their writing or understand what's going on, you should usually assume it's wrong.
• Be suspicious: If you see similar, very wrong answers, flag the tests and compare their answers to other questions. Hopefully you can look out for cheating while the quiz/exam is actually going on, but you won't be able to see everything.
• Talk (probably through e-mail) to students in your section(s) who performed very poorly (grades of less than 40% or 50%). They may be too shy to ask for help even if they know they need it!

• You'll grade these kinds of tests with your fellow GSIs.
• Have a few people people double-check the answer key Scantron for each version of the exam BEFORE you start running all the tests through the machine.
• Note any questions that are missed quite frequently. Reasons for this can include:
  • The question was poorly written or possibly too hard
  • The students just didn't know that material very well
  • There's an error on the answer key
  • Something went wrong with the machine or the answer key Scantron
• Note any one student who missed a TON.. Reasons:
  • They really just don't know what's going on
  • They marked the wrong test version (you might be able to re-run it through the machine with the correct answer key or their GSI or the Head GSI might have to grade it by hand)
  • They used some writing utensil that the machine doesn't like (their GSI or the Head GSI might have to grade it by hand)
  • Their test is too wrinkled or has coffee spilled on it or whatever (their GSI or the Head GSI might have to grade it by hand)
  • Use your judgment here; it's annoying to grade a Scantron by hand, but if they really just accidentally spilled something on it, then you should probably grade it by hand with no penalty. If they're dumb enough to mark the wrong test version, well, they might deserve some extra points off for that.
• It's a good idea to skim over each of your student's tests to see if there were any obvious bad erasure marks or anything like that which may have led to an answer being marked wrong unfairly. However, don't feel bad if you don't catch every one of these – your students will not miss any!!
• Like after quizzes, strongly consider talking to students in your section(s) who performed very poorly (grades of less than 40% or 50%).

• Usually not the GSI's responsibility to grade.
• Basically, all of the above rules apply.
• Cheating is certainly more of an issue since you can't watch everyone do their homework, so beware! As mentioned before, hopefully the graders will flag any possible cases of cheating and then you can take a closer look at the actual assignments and decide whether or not any academic dishonesty actually occurred.

• You should come up with some objective grade calculation (unless one is already provided to you by the prof and/or Head GSI).
• A grade for Discussion Section might include (ONLY if these aren't assigned grades on their own elsewhere in the course grading rubric):
  1. attendance in section
  2. participation in section (group work, coming up in front of the class, asking the GSI questions, worksheet diligence, etc.)
  3. in section quiz(zes)
  4. star party attendance
• Usually this isn't a huge part of the overall course grade, but it's sometimes a non-zero amount of points and you should be fair and consistent about assigning them.
• With that said, if someone really went above and beyond and worked really well in section, usually you have the authority (as long as it's cool with the prof and/or Head GSI) to give them a little something extra in their section grade (though you probably shouldn't give them over 100% of the section points).
• On the other end of things, sometimes students with borderline grades will try to wring a few extra section points out of you to push their grades up to the next letter.

• Usually GSIs don't have much control over this. However, GSIs occasionally help decide the course grading rubric before the semester starts.
• The course grading rubric should be well-defined and a (relatively) simple calculation.
• It should be spelled out in detail on the syllabus (which should be handed out or posted online at the very beginning of the semester).
• Converting numbers to actual letters is the hardest (and usually the most mysterious and opaque to students) part of this process.
• Finally, most profs/Head GSIs will let each GSI have a small amount of discretion in final letter grades (with pluses and minuses) for their students who are right near a letter grade cutoff.
  • Most profs/Head GSIs will try to choose the cutoffs such that no one is close to any of the boundaries.
  • However, this discretion is fairly common practice since the GSI should know the student (and their performance in the course) better than either the prof or Head GSI.
  • Thus the GSI can use the student's performance in their section to decide whether or not to bump them up above or below the cutoff.
  • With that said, unless the student was absolutely horrific in section, GSIs should probably never bump anyone down below a cutoff!

1. If you have not scheduled a time for us to chat about your video, do so.
2. Remind them that we will be doing board work exercises again the next two weeks. But this time you won't know what questions are coming (they will be related to your particular course's material).