Labs, Demos and Activities

► Estimating Pi (do this in EXCEL) do this in EXCELdo this in EXCEL ► Fun with Fives! ► Measuring the speed of sound ► Mystery Toy! ► Quick look at DLOs as Lab DLOs

So…Why do labs? The “less is more” slogan in Benchmarks for Science Literacy (AAAS,1993, p. 320) has been articulated to guide curriculum development and teaching consistent with the contemporary reform. The intended message is that formal teaching results in greater understanding when students study a limited number of topics, in depth and with care, rather than a large numbers of topics much more superficially, as is the practice in many science classrooms. Hofstein & Lunetta 2003

Finally, it is disappointing to note the continuing limitations in systematic scholarship associated with such a central medium as the laboratory in science education. There is new information about limitations in the effectiveness of school science education; there also continue to be important reasons to believe that school laboratory activities have special potential as media for learning that can promote important science learning outcomes for students; teachers need knowledge, skills, and resources that enable them to teach effectively in practical learning environments. They need to be able to enable students to interact intellectually as well as physically, involving hands-on investigation and minds-on reflection;practical learning environments students’ perceptions and behaviors in the science laboratory are greatly influenced by teachers’ expectations and assessment practices and by the orientation of the associated laboratory guide, worksheets, and electronic media; and teachers need ways to find out what their students are thinking and learning in the science laboratory and classroom.

Are these comments similar to… ► The claims about using DLOs? ► Do both the alleged claims about Laboratory and DLO benefits suffer from similar problems ie – they sound like they should work but it is really hard to “prove it”?

… Factors that continue to inhibit learning in the school science laboratory include thefollowing: Many of the activities outlined for students in laboratory guides continue to offer “cook-book” lists of tasks for students to follow ritualistically. They do not engage students in thinking about the larger purposes of their investigation and of the sequence of tasks they need to pursue to achieve those ends. Assessment of students’ practical knowledge and abilities and of the purposes of laboratory inquiry tends to be seriously neglected, even by high stakes tests that purport to assess science standards. Thus many students do not perceive laboratory experiences to be particularly important in their learning. Teachers and school administrators are often not well informed about what is suggested as best professional practice, and they do not understand the rationale behind such suggestions. Thus, there is a high potential for mismatch between a teacher’s rhetoric and practice that is likely to influence students’ perceptions and behaviors in laboratory work. Incorporating inquiry-type activities in school science is inhibited by limitations in resources (including access to appropriate technology tools) and by lack of sufficient time for teachers to become informed and to develop and implement appropriate science curricula. Other inhibiting factors include large classes, inflexible scheduling of laboratory facilities, and the perceived foci of external examinations.

What’s the Distinction Between… ► Lab ► Demo ► Activity Which is “best”? Major Task: Devise/select a Lab, Demo or Activity that illustrates a topic you wish to address – work this into a lesson that you will teach in your practicum. You may have more than one but will need to establish what specific goal(s) you hope to achieve (why bother with it?) and how you propose to determine whether or not is was educationally useful.

Group Challenge! ► Task 1: Present a geometric demonstration that ► Task 2: Create Pascal’s Triangle and show how this relates to polynomial expansions ► Task 3: Investigate the pattern in (11) n and show how Pascal’s Triangle can be used as a calculator