The Irish white commonly used in North America can be divided into three principle types: red-, russetand white-skinned. These types have different characteristics that result in different uses by consumers and processors (Pavlista 1996). The following number of simple exercises demonstrate potato tuber characteristics and are designed for high school biology students and teachers. They were modified from methods used commercially (Draper et al. 1979; Gould 1980; 1985; Gould & Plimpton 1985) or were developed as demonstrations. These exercises work best when used in conjunction with the discussion lesson (Pavlista 1996) and with students divided into groups. The first and most crucial requirement is to have samples of the potato types: red-, russetand white-skinned tubers. The whiteskinned tubers obtained from a market probably will not be quality but can be used for demonstration purposes. If there is a chipping plant or a chip grower in the vicinity, obtain white-skinned tubers from them. Fresh tubers are preferred; therefore, autumn is the best time for these exercises. Purchase a tuber of each of the three types for each student. At least 4.5 kg (10 lb) of each potato type per group is preferred. The following exercises are noted with respect to a degree of difficulty-Basic is for sixth grade and up; advanced is for ninth grade and