Summary:
This article describes a three year study focused on training physical science high school teachers to incorporate guided inquiry labs into their practice. A major focus was on workshops where teachers could practice inquiry based labs and learn about how to structure similar labs in their classrooms.
The researchers found the while guided inquiry labs were used more often, there were barriers to implementation such as time constraints, pressure to structure classes to complete the course, pressure to prepare students for state level testing, and difficulties associated with motivating all students to participate in inquiry.
Finally the authors conclude that:
"There is no silver bullet for inquiry: Science educators need to have patience and understand the factors that impede implementation and transition to inquiry."
The article also included a useful example of a guided inquiry lab, as well as a structure for guiding post lab discussion. Both are reproduced below.
A guided inquiry lab in physical science/chemistry
Hint for teachers: this is not a lesson plan. You will develop flexible lesson plans for teaching this topic after you do the investigation yourself. Identify the national and state science education standards. This guided inquiry lab is to be done by students with minimal teacher support. So, have patience and help students to explore and come up with their own questions, results, and possible explanations. Provide hints/help when needed.
Objectives:
- To understand the process of investigative approach to science inquiry
- To understand how knowledge of content and skills are important to conducting inquiry processes
- To identify content, process, and nature of science standards which could be taught using this lab
Guide inquiry procedure:
- Take a piece of magnesium ribbon & identify physical properties before burning
- Observation is a very important step in science inquiry. You will make observations while doing this lab. What equipment do you need? (Mg ribbon, tongs, test tubes, dilute HCl, watch glass safety goggles)
- Burn the magnesium and record all observations.
- What questions do you have based on these observations? Write them down. (Lead questions: What are the major observations? Is burning Mg a chemical or physical change or both? Is the product different from the reactant mg metal?)
- Selecting one question at a time, discuss these topics in your group and suggest a method and procedure you could use to investigate that question. Discuss your proposed methods with the teacher and finalize your plan.
- Question: Is the product different from reactant Mg metal? Place small amounts of Mg metal and the product left after burning in two separate test tubes. Add 10 drops of diluted HCl acid to each test tube. Observe and record what happens. (Hint - possible observation - gas comes out when Mg metal reacts with HCl but no fizzing takes place with the product. The gas released is hydrogen. To verify this, put a burning match over the mouth of each test tube. If hydrogen gas is produced a popping sound will be heard.)
- What are your inferences? Does the product contain Mg metal? (No - not in it's metal form)
- Question: What does the product contain? Does it contain Mg in some other form? If yes, in what form? (Discuss this topic in groups and then generate a whole class discussion. What do we do to investigate the possibility that Mg is present in some other form in the product? Discuss with students the need for content knowledge and abilities to engage in inquiry. Then demonstrate to students a lab test that detects Mg ions in a known sample and perform the same test on the residue left after burning Mg. If the test shows the same results in both known and unknown samples, what do you infer?
- What do you conclude?
- Challenge students to come up with a possible explanation of how the Mg metal became the Mg ion in the solid product after burning in air. Is this a chemical or physical change?
- Use this lab to develop concepts of chemical and physical changes, chemical reactions, ionic bonding, and the transfer of electrons from Mg to O2 during the formation of MgO.
Post lab discussion
- Organize a post-lab discussion for 30 min after each guided inquiry lab.
- First, organize group discussion on lab results and interpretation, followed by presentation of group reports to the whole class.
- Ask students why different groups think different ways and how they would resolve the differences. Encourage each group to synthesize their findings and conclusions based on whole class discussion.
- Then you (the teacher) should summarize the post-lab discussion and offer your ideas/comments, being sure to connect the inquiry -based lab activities to the academic content being covered.
- Wrap up post-lab discussion with questions such as:
- What are "data" in your lab today?
- What are the evidences you collected?
- If a scientist were to perform the lab you did today, would he/she complete it in the same way? If not, what do you think the scientist would do? (Hint - scientists follow similar procedures to discuss and share their viewpoints)
- Do you see any similarity between you and a scientist? (Both raise questions, hypothesize, design experiments, collect data and evidences, and develop explanations/theories.)
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