Shared teacher planning time may be a critical support for improved laboratory teaching, because of the unique nature of laboratory education. As we have discussed, teachers face an ongoing tension between allowing students greater autonomy in the laboratory and guiding them toward accepted scientific knowledge. They also face uncertainty about how many variables students should struggle with and how much to narrow the context and procedures of the investigation. When one college physics professor taught a high school physics class, he struggled with uncertainty about how to respond to students’ ideas about the phenomena they encountered, particularly when their findings contradicted accepted scientific principles (Hammer, 1997). In a case study of his experience, this professor called for reducing science teachers’ class loads so they have more time to reflect on and improve their own practice.
A supportive school administration could help teachers overcome their isolation and learn from each other by providing time and space to reflect on their laboratory teaching and on student learning in the company of colleagues (Gamoran, 2004). In this approach, school administrators recognize that leadership for improved teaching and learning is distributed throughout the school and district and does not rest on traditional hierarchies.
In 2000, according to a nationally representative survey of science teachers, most school administrators provided inadequate time for shared planning and reflection to improve instruction. When asked whether they had time during the regular school week to work with colleagues on the curriculum and teaching, 69 percent of high school teachers disagreed and 4 percent had no opinion, leaving only 28 percent who agreed. However, 66 percent of teachers indicated that they regularly shared ideas and materials with their colleagues, perhaps indicating that they do so on their own time, outside school hours (Hudson et al., 2002). Only 11 percent of responding teachers indicated that science teachers in their school regularly observed other science teachers. Among teachers who acted as heads of science departments, 21 percent indicated that the lack of opportunities for teachers to share ideas was a serious problem for science instruction (Smith et al., 2002).
Time constraints can also discourage teachers from the challenges of setting up and testing laboratory equipment and materials. Associations of science teachers have taken differing positions on how administrators can best support teachers in preparing for and cleaning up after laboratory experiences. The American Association of Physics Teachers (AAPT) suggests that physics teachers should be required to teach no more than 275 instructional minutes per day. Many schools schedule eight 40- to 55-minute class periods, so that following the AAPT guidelines would allow physics teachers two preparation periods. The guidelines also call on administrators to schedule no more than 125 students per teacher per day, if the teacher is teaching only physics (the same laboratory activity taught several times may not require preparation) and no more than 100 students per teacher per day if the