The assessment of inquiry-based projects varied greatly across participants. Each teacher participant evaluated a set of three inquiry-based science projects that differed in their quality, and this variation increased when the inquiry-based projects were compared across participants. The inquiry-based science projects varied in their degree of complexity, sophistication, originality of the topic, and method of investigation. The projects originating from Edward teacher's instruction were qualitatively superior to those assessed by the Novice-Expert and Novice-Novice teachers. In addition, these inquiry-based projects were the only projects that addressed the criterion of originality.