The practice of RNA isolation in undergraduate experimental courses is rare because of the existence of robust, ubiquitous and stable ribonucleases. We reported here modifications to our original protocol for RNA isolation from plant tissues, including the recovery of nucleic acids by ethanol precipitation at 0 degrees C for 10 min and the assessment of RNA quality by visualizing the banding profile of the separated RNAs on a standard nondenaturing agarose gel to shorten the duration of the whole procedure and simplify the operation. As a result, the modified procedure, including RNA isolation and quality control analysis could be finished in 4 hr and divided into two sessions. Because endogenous ribonucleases released upon disruption of the organelles and vacuoles were effectively and quickly inactivated, measures were taken to protect RNA integrity throughout the whole procedure so that total RNA with high purity and integrity as well as an appropriate yield could be obtained by students. The RNA isolation protocol described here was simple, efficient, flexible, and low cost. Therefore, it is an ideal approach for undergraduates to learn about RNA techniques. The pedagogical approach of the correlation of experimental work with the rationale for the whole protocol described in this report is an effective way for undergraduates to improve their learning of the techniques of RNA isolation and analysis and the theories behind them, as well as experimental design and data analysis.