Ms. Jentzen then told the students to behave like “a class of
research scientists” and to build their own diver systems. She
explained that the diver was a good example of something that
sinks and floats, and asked them to determine, “Why or how can
it do that?” The students then constructed their own diver
systems in pairs of two. Don constructed a working CDS in
three attempts and was able to assist another student at his table
to construct one as well. After constructing a working system,
Don was reluctant to set it down or to end the investigation,
stating, “I’m trying to figure out how this works by looking at
it.” In his lab notebook, Don wrote “I Thank you pis don it gobo
up” and drew a picture of the CDS (see Figure 2).