Using Modern Tools to Update the Organic Chemistry Laboratory Laurie S. Starkey Chemistry Department California State Polytechnic University, Pomona 3801 West Temple Avenue, Pomona, CA ~ lsstarkey

About CHM 317L 1st quarter of year-long Organic Chemistry Laboratory sequence 11 sections per year, ≈180 students per year, up to 24 students per section Laboratory Exercises: melting pointTLC extractiondistillation recrystallizationIR spectroscopy (+ synthesis capstone experiment)

About the Students Type A wants to learn, asks questions/seeks answers, thorough understanding of concepts Type B does required work, competent, good understanding of concepts Type C does minimally acceptable work, cookbook, weak understanding, many misconceptions Type D copies someone’s prelab minutes before lab, relies on partner, won’t act independently Goal: Mostly A’s, the rest B’s

The Obstacles Limited lab time –one 3-hour lab per week Limited grading time –meaningful feedback = instructor’s time Delayed feedback –Wk1 lab, Wk2 turn in report, Wk3 get grade Lab textbook format –no discussion of common mistakes, no answers to end-of-chapter questions

Possible Solutions (w/Drawbacks) Discovery-based exercises –limited applications for lower-division labs –expensive ($0.60 per TLC plate) Weekly recitation sections –overload of units –politics of support courses Problem-based Textbook w/Solutions Manual –does one exist?

Online Prelab Quizzes Make use of time outside of lab Ask questions, give answers –what makes the right answers right? –what makes the wrong answers wrong? FEEDBACK, FEEDBACK, FEEDBACK! –immediate and abundant Explore common mistakes, misconceptions –BEFORE coming to lab!

WebCT - Advantages Accessible from home, library, campus Easy to add all students (uses course ID#) Many quiz settings and options –multiple attempts allowed (or not) –make quiz available on a certain date –take Quiz 2 only after passing Quiz 3 Automatic grading and Gradebook entry Print out quiz attempts with feedback

WebCT - Disadvantages Who is taking the quiz? –administer brief in-lab quiz Quarterly maintenance, Site license –need a lab coordinator (1-2 h per quarter) –self-registration can be enabled Files must be loaded one at a time –can zip/unzip multiple files Non-sizeable frames  small viewing area Occasional incompatibilities, bugs

Results Students are better prepared Students make fewer mistakes Students ask more in-depth questions Last-minute prelabs are eliminated Best results if quizzes factor into grade