The effects of kinetic vs thermodynamic control on "endo"/"exo" stereoisomer ratios can be observed in a simple Diels-Alder reaction between "N"-phenylmaleimide and furan. The use of microwave-promoted synthesis affords the cycloadducts in yields ranging from 65-100%, employing reaction times of 1-10 min at temperatures of 55-130 °C. Short reaction times enable screening of numerous reaction conditions (time and temperature) within a single lab period, where "endo":"exo" product ratios follow the primary facets of kinetic and thermodynamic control. Analysis of product ratios obtained under kinetic control allows for the evaluation of activation parameters ([delta][delta]"H"[thermodynamic] ([approximately equal to] [delta]"E"[subscript a]), [delta][delta]"S"[thermodynamic], and [delta][delta]"G"[thermodynamic]) by means of the Arrhenius and Eyring equations. Values of [delta][delta]"H"[thermodynamic], [delta][delta]"S"[thermodynamic], and [delta][delta]"G"[thermodynamic] were found to be 6.4 ± 0.3 kJ mol[superscript -1], 16.5 ± 0.9 J mol[superscript -1] K[superscript -1], and 1.5 ± 0.4 kJ mol[superscript -1] ([delta][delta]: "exo"-"endo"), respectively. Experimentally determined activation parameters correlate well with quantum-chemical calculations. Several key teaching points are also addressed, including frontier molecular orbital analysis, reversibility of the Diels-Alder reaction, column chromatography, and the use of [superscript 1]H nuclear magnetic resonance spectroscopy to assess both stereoisomeric yield and purity.