200 likes | 542 Views
Chapter 8: Laboratory and Field Work Objectives: Define and give purpose for lab and field work 2. Discuss and construct exercises in five lab approaches 3. Discuss elements of pre- and post-lab discussions 4. Describe teaching tips for successful labs 5. Plan productive and safe field trips.
E N D
Chapter 8: Laboratory and Field Work Objectives: • Define and give purpose for lab and field work 2. Discuss and construct exercises in five lab approaches 3. Discuss elements of pre- and post-lab discussions 4. Describe teaching tips for successful labs 5. Plan productive and safe field trips
Defining Laboratory Work • Engages students in finding out first hand • Involves asking questions, making observations, proposing solutions, making predictions, organizing data, explaining patterns • Can be used to improve technical skills • May involve specialized equipment • Central to science instruction • Shows students what scientists actually do • Develop a better understanding of concepts and principles • Provides concrete experiences • Promotes: • Attitudes towards science • Scientific inquiry • Conceptual development • Technical skills • Concerns • Often aimless, trivial, and badly planned • Periods too short, students often don’t complete the lab, lack materials • Should promote inquiry, not be “cookbook” only
Approaches to Laboratory Work • Science process skills • Learning skills, not content, is sometimes the primary goal of a lab • Often addressed at the beginning of a science course • Mental processes associated with science: a. Observing and Inferring i. p. 152 gives an example exercise ii. Observing = noting something with senses or an instrument iii. Inferring = explaining what you observe b. Measuring: p. 153 give creative example of a practice exercise c. Hypothesizing = general statement about set of phenomena d. Communicating e. Experimenting = trying something out i. Can be controlled, where only one variable is allowed to change ii. Independent variable = what is changed • Dependent variable = what you are measuring • Deductive or Verification Lab • Confirm concepts already presented in class • Convince students through concrete, personal experience • Try to avoid cookbook by allowing some freedom to try things
Inductive Laboratory • Develop experience with a concept before formal instruction • Students search for unknown patterns and principles • Example box 8.2, figure 8.4, and figure 8.5 • Learning cycle (5E lesson plan) exploration step prior to explanation encourages the use of inductive labs • Technical Skill Laboratory • Manipulative and hand-eye coordination skill important to science • Teachers should master all skills in the content area (p. 158) • Examples: • Care and use of microscopes is very important to biology students • Measuring voltage and current important in physics • Diagrams, graphs, drawings are important in all sciences • Struggling with basic skill impedes learning concepts in lab • Problem-Solving Lab • Allow students to participate in selecting problem (insect to study) • Students typically understand better when organizing own learning • Can serve to motivate low or high-achieving students
Preparing Students for Lab • Pre-lab discussion • Inform students why, how, and what they will be doing • Should explain how lab related to topic currently under study • If inductive lab, don’t give away the principle • May include demonstration of new techniques or equipment • Labs are less cookbook if student know what to look for • Giving directions • Need to be explicit and contain safety information • Oral instructions are fine for one-step activities: test pH with paper • Distribute written instructions or write on chalkboard if complex • May include questions for students to answer at certain points • Post-lab discussion • Often rushed or ignored due to lack of time • Critical to students crystallizing what they have learned
Suggested post-lab activities • View and analyze data and observations • Have students explain data and how it demonstrates concepts • Check student misconceptions; they don’t always “get it” • Discuss science process skills to connect lab with science/technology • Teaching Tips for Successful Labs • Relevance of Lab work • Lab can become disconnected from course content, everyday lives • Use of commonplace equipment (xylophone, candles, household chemicals) provide connection to reality (Rubin, 1988) • Make sure lab is tied to content taught in other ways • Structure in Lab activities • Short exercises with plenty of direction seem to work best at first • Students become frustrated if they “don’t know what to do” • Some less structured labs facilitate problem solving, conceptual change, and motivation. Can be incorporated later in a course.
Student Recording and Reporting of Data • Try to keep is simple so most time is spent on the experiment • Most manuals provide space for student data collection • Should vary, just as complexity of labs vary • Open-ended or inquiry labs may require more in-depth reporting • Typical format: problem, materials, procedure, results, conclusions • Often quite time-consuming to grade • De-emphasize correctness of data and conclusions, emphasize process skills • Management and Discipline • Arrange for enough space and to keep materials away until needed • Individual work is best, but not always feasible • Groups often promote off-task activities: assign roles • Noise can be a problem in the less structure lab environment • Continuous contact with teacher can help: walk around, don’t sit • Rules and policies should be developed and discussed prior to lab • Example set of policies p. 165
Evaluation • Items to grade: lab exams, reports, notebooks, behavior, effort • Lab exams should be short and should reinforce concept learning • Lab practicals = stations with skills, techniques evaluated • Effort and behavior should count significantly, especially in middle school • Field Work • Contributes to scientific literacy • Authentic learning experiences • Often the most memorable and enjoyable activities • Planning a Field Trip • Hospitals, power plants, factories, wildlife refuges are possibilities • Selection must be based on connection to curriculum • Survey possible sites prior to trip; often areas right around the school can provide natural environment needed (p. 167) • Consult administrators for permission and policies • Make sure students know exactly what to do once in the field • In-class activities before and after maximize educational benefits