Site Map

Advanced Conceptual Workshops


Guidelines for Writing  Problems

Goals
1. Difficulty Level
The problems should NOT be seen as remedial and must not be primarily a review of very basic material.  Why?  Students need to see that they and their abilities are respected: the role of the teacher expectations on student performance is well known.

2. Relevance
It is essential that students see the worksheet problems as relevant to the course. The problems must not be seen as something extra and unrelated, but as something that is directly helpful to the students in improving their performance in the course.  Problems may be chosen to
•  help students understand a difficult concept.
•  reveal students’ misconceptions and help them construct a correct understanding.
•  expand on concepts or methods stressed in lecture.
•  address questions posed in lecture, or
•  address unanticipated misconceptions that came to light as students work on previous worksheets.

Primarily, you should ask yourself, what paradigms are students likely to hold that you will want them to challenge or reject?  How can you put them in a situation intellectually in which those paradigms don't work, in which they face what one psychologist called an "expectation failure?"   Think about the new paradigm that you want students to construct as a result of struggling with the problem.


3.  Interest Level
Another goal of the Advanced Conceptual Workshop program is to heighten students’ interest in the sciences. Therefore, you should choose problems that are fascinating to your students.

4.  Discussion Level
The final goal in writing workshop problems is to consider the amount of discussion the problems will generate.  All problems should be designed to promote discussion and interaction among students.

5.  Concept Rich
The problem should involve some important concept.


 
Structure
You could begin with a relatively easy problem as a kind of ice-breaker, but each session should have at least one extremely challenging, interesting, conceptually-rich problem. 

Remember, students are most likely to learn deeply when they are struggling collaboratively with problems or questions that they (not you) find important, intriguing, or beautiful, and they can do so in a supportive environment in which they can try, fail, receive feedback, and try again without anyone making a judgment about their abilities.

(These guidelines were developed by Ken Bain, Ph.D. from material developed as part of the GSW program at Northwestern University, which were distilled from ideas developed by James A. M. Epperson Ph.D. for the Emerging Scholars Program at the University of Texas, Austin.)

Back to Top

Some additional Advice from Northwestern's Gateway Science Workshop Program (GSW):

“No mortal will ever solve all of the problems”
  •  It is important to build a culture around this idea and let students know that faculty can create problems that all of them can do, some of them can do or none of them can do. This will combat the idea that “either I can do science or I can’t do science.” 
  • Create opportunities to discuss obstacles.  What can you infer from getting the correct answer?  Only having problems that are too hard will only frustrate them and make them think they are not good enough to be here. Include both easy and very hard problems on worksheets.
  • Creating confusion:  Putting hard problems on worksheets will remind students that this is the position they will be in all of their careers.
  • Students need concrete ideas about what “playing around” means and could do for them.  This will change their orientation to challenge because they will understand that all of us spend a lot of time being confused.
Evaluating Problems
  • Faculty should build tools that capitalize on the knowledge they build in the classroom.
  • Consider the level of difficulty of each problem.
  • Deeper learning doesn’t only mean harder questions.
  • Ask what issues are addressed and the level of difficulty of the problem. What is the purpose of the problem
Training during weekly meetings
  • Faculty should try and model the facilitation process during the weekly meetings.
  • Facilitators do not always grasp the material they will be facilitating.
Ideas for training sessions
  • Introduce problems, offer a brief review & leave the room to let facilitators work on their own. Return to check on progress.
  • Pass out worksheets and allow facilitators to work through problems. Pass out answer keys once facilitators have finished working on problems.
  • Have Senior Facilitators create weekly problems themselves.
  • Send questions to facilitators early and ask them for critique and feedback.

Back to Top

Biology 210 Sample GSW questions (from Northwestern University
1.    In a hospital laboratory, a 10.0 ml sample of gastric juice (a strong acid) was titrated with 0.1 M NaOH to neutrality; 7.2 ml of NaOH was required.  The patient from whom the gastric juice was obtained had not ingested food or drink, so no buffers were present.  What was the pH of the gastric juice?

2.    Last year, the anti-inflammatory medicine Vioxx was pulled off the market when it was found to increase the risk of heart attacks and strokes.  Most anti-inflammatory drugs are absorbed into the blood through cells lining the stomach and the small intestine.  Absorption requires passage through the cell membrane, which is determined by the polarity of the molecule: charged and highly polar molecules pass slowly, whereas neutral, more hydrophobic ones pass rapidly.  You have secured a research position at a large drug company, Big-Money pharmaceuticals, and you have been given the task to develop a new drug to replace Vioxx.  Below you will see two molecules: the one on the left is Vioxx and the one on the right is a Vioxx derivative called NUoxx.  You can see from the figure that Vioxx is uncharged and only slightly polar so it is absorbed efficiently in the stomach, but worry that NUoxx may not be absorbed efficiently (the pKa of the –OH group is 3.8). You’ve already calculated the pH of gastric juice in the stomach and it is known that the pH of the small intestine is about 5.  Is more NUoxx absorbed into the bloodstream from the stomach or from the small intestine?  Why? 



Calculate the percentage of the unionized form of NUoxx available for absorption in the stomach and in the intestine (pH 5.0).

3.    As you remember from Problem Set #1, NUoxx is believed to inhibit the production of prostaglandins from arachidonic acid via the cyclooxygenase-2 enzyme.  Prostaglandins are produced in response to tissue injury and cause inflammation and fever. Given the concentrations of prostaglandins and arachidonic acid are 60mM and 25mM respectively, using ΔG°’, prove that the reaction (production of prostaglandins) is spontaneous at 37 °C? 


4.    You are now set to further characterize NUoxx as an anti-inflammatory drug and a replacement for Vioxx.   You previously determined that NUoxx, is absorbed efficiently in the stomach.  You have also now determined that the production of prostaglandins from arachidonic acid via the cyclooxygenase-2 enzyme is spontaneous.  Now, you need to further characterize the kinetics of cyclooxygenase and its interaction with NUoxx before starting any human trials. 

First, you do some classic Michaelis-Menten kinetics.  You set up an experiment and vary the amount of arachidonic acid with fixed enzyme concentration.  The data for that experiment is found below.

 Estimate the value of KM for this reaction

Use the Michaelis-Menten equation to determine the velocity of the reaction when the concentration of arachidonic acid is 0.003 mM (physiological concentration).

Next, you run the enzyme assay using 0.00025 mM arachidonic acid and 10 mM NUoxx and you find that the reaction is completely inhibited.  If you setup the reaction using 0.003 mM arachidonic acid and 10 mM NUoxx you find that the reaction has a rate of 30 mM/min.  What type of inhibition is NUoxx exhibiting?

For NUoxx to be effective, the velocity of the reaction needs to be reduced to 10% of the velocity at physiological concentrations of arachidonic acid.  In order to achieve this target, what should the concentration of NUoxx be?   Assume that the KI is the same as the KM. 


Additional Sample Problems in Calculus from Northwestern's Program
The Research Academy for University Learning at Montclair State University - Montclair, New Jersey, 07043, USA
| 973-65-LEARN (655-3276) | Teach-Learn@mail.montclair.edu | Ken Bain, Director