The Hawthorne and placebo effects in educational experiments were examined over a 20-year period, as reported in the ERIC, Dissertation Abstracts International, and Psych Info data bases. The literature searches identified 325 studies in education employing the relevant control procedures, and each study was coded for the type of placebo procedure, its estimated phenomenological impact, the rationale and label for the control group, and whether the procedure's placebo-like qualities were identified/documented. In addition, studies were classified by: (1) educational research topic area; (2) subject age and type; (3) number and nature of treatments; (4) presence and type of no-treatment controls; (5) subject sampling procedures; (6) experimenter characteristics and assignment; and (7) use of blind experimenters or other controls for bias. In most studies, irrelevant or substitute activity was used as the placebo control. In others, the placebo procedure closely resembled treatment, but with no element of treatment administered. In some of these studies, a substantive element of the treatment procedure was included in the placebo procedure. Other studies used minimal contact as the placebo. The rationale, if stated, for use and design of placebo was usually to guard against Hawthorne effects or to compensate for differential concerns, usually attention, activity, novelty, or interaction. The design of placebo groups showed subjects' hypothesis awareness and expectancies were not a major focus of the reviewed research. (MGD)