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The technology of nuclear magnetic resonance spectroscopy h a s changed dramatically i n recent years. Whereas 15 years ago 'H NMR spectra ohtained a t 60 MHz were routine, even for most research samples, todav hieh-field 'H and 13C NMR mectra have become the " norm. The added sensitivity and dispersion obtained by high field, Fourier Transform instruments, and the significant additional information provided by lSC NMR spectra, coupled with advances in super-conducting magnet technology, have led to a revolution in instrumentation.This revolution h a s left institutions in a dilemma with respect t o use of NMR i n introductory organic chemistry courses. Many undergraduate institutions have been priced out of the NMR market altogether and can offer their students no hands-on NMR experience. Others continue t o nurse alone 20-vear-old 60 MHz spectrometers, and their students never have the opportunitv to work with hieh-field s~e c t r a .Research universitiesand many research-active colleges have high-field s~ectrometers. but do not or cannot provide access to intioductory stidents, because use o i the instrument reauires extensive training, and data acquisition is too time-consuming to allow ;'large group ofstudents to acquire spectra during a typical laboratory period. A few institutions have responded to these problems by having students prepare the samples and then having a n advanced student, teaching assistant, or technician obtain and plot the spectra. This approach has the advantage that students have the opportunity to analyze spectra of real samples, but the disadvantage that students have no hands-on experience with NMR.Situation at Grinnell College NMR soectroscoDv is covered in the middle of the first semester of the organic chemistry course, when students have mastered enough structural chemistry to make use of it. Students are taught to interpret NMR spectra, along with infrared and mass spectra for use in structural elucidation problems. The mos't intensive and effective learning goes on during the second-semester lahoratory, which consists of 10 weeks of qualitative analysis where students determine the identities of several single and mixture unknowns. Students measure standard physical properties, conduct simple functional group tests, and prepare a derivative of each unknown. They also record IR spectra and interpret NMR spectra of their unknowns. Students report the identities and supporting evidence for their unknowns in oral reporting sessions with their instructor. At this uoint the instructor not onlv listens to the evidence and ionclusions, hut also students on their interpretation. I t is here where we find the most effective learningof NMR occurs. When we had a 60-MHz spectrometer, we handed out a ohotocouv of the a m r o~r i a t e soectrum with each unh w n . in 1986, the' ?Ai;?nell ~o i l e~t ! Chernlstry Dcpartment redaced its 60-Mflz-'11-FT soectrometer with a 300-MHz in'strument. Because the time required to obtain a spectrum on the previous instrument was long, we had maintained a ...

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