Many science educators have advocated the use of hands-on activities, involving materials and phenomena, for teaching abstract science concepts and related science processes at the upper elementary and middle school levels. The major effort to implement these prescriptions has been through the development and dissemination of instructional programmes. The primary method utilised for determining the teacher's intentions was the analysis of the teacher's planning. This involved video-taping the teacher while she was engaged in planning for instruction. The planning practices described by Ms Ross, however, led us to consolidate the several into two types, each fundamentally different from the other and suited to different purposes. The after school discussion with Ms Ross of the day's activity revealed that her conception differed from that addressed by the activities. The literal programme indicated discussion in which the students are to identify the bubbles and support their answers with evidence from the results of the gas generator demonstration.