Separating Mixtures
“An ‘investigation’ is often seen as an experimental study that requires first-hand student participation and leads towards providing evidence that permits a question, that was posed at the beginning, to be answered” (Lock, 1990).
Practical work is an essential component of science in schools (Venville and Dawson, 2004). ‘Open-ended’ or ‘inquiry-based’ investigations are those that require students to ‘think for themselves’ to design, conduct and evaluate an experiment. This is in direct contrast to the traditional recipe-driven experiments that have plagued our classrooms in the past. This type of investigation provides students with the opportunity to learn from trial-and-error, to act as ‘real’ scientists do and to discover for themselves the nature of science. Through this process students are actively engaging in science, developing their critical thinking and problem solving skills and making relations to the world around them (Venville and Dawson, 2004). They get to make decisions for themselves rather than being told what to do by the teacher. As such they take more responsibility and ownership of their investigations
It has been suggested that there are three main purposes for practical work; to develop understanding of concepts, to develop practical, manipulative skills and to educate students in the process of inquiry (Lock, 1990). The ‘aim’ of the investigation should not always be to arrive at the correct answer or to have the most accurate results but rather to have actively engaged in the investigative process itself.
Open-ended investigations provide opportunities for students to work in collaboration and cooperation with each other. This opportunity for shared thinking and questioning has been shown to promote deeper thinking and helps to instill in the students a passion for life long learning (Black and Williams, 2001).
Despite the many benefits of open-ended practical investigations many teachers may be reluctant to engage their students in this type of practical work. This is primarily due to the increase in time and resources required for students to plan and conduct the activity. Additionally, some students may be reluctant to participate in open-ended practical investigations as they lack the planning skills and confidence required to design their own experiment (Venville and Dawson, 2004). In these situations teachers need to provide students with the appropriate support and scaffolding to guide them through this process.
This open-ended practical investigation that I have developed is one that could be implemented with year 7 students. The Australian National Curriculum states that at this level students should learn “Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques” (ACARA, 2012).
The practical investigation would be done toward the end of a teaching sequence on ‘particle theory’. The students should be provided with adequate background knowledge of particles and the means by which they can be separated. These methods include solubility, magnetism, buoyancy and particle size.
At this year level, teachers should go over a number of lab safety procedures and rules to ensure that all students are aware of the expectations before they commence their investigation.
Practical work is an essential component of science in schools (Venville and Dawson, 2004). ‘Open-ended’ or ‘inquiry-based’ investigations are those that require students to ‘think for themselves’ to design, conduct and evaluate an experiment. This is in direct contrast to the traditional recipe-driven experiments that have plagued our classrooms in the past. This type of investigation provides students with the opportunity to learn from trial-and-error, to act as ‘real’ scientists do and to discover for themselves the nature of science. Through this process students are actively engaging in science, developing their critical thinking and problem solving skills and making relations to the world around them (Venville and Dawson, 2004). They get to make decisions for themselves rather than being told what to do by the teacher. As such they take more responsibility and ownership of their investigations
It has been suggested that there are three main purposes for practical work; to develop understanding of concepts, to develop practical, manipulative skills and to educate students in the process of inquiry (Lock, 1990). The ‘aim’ of the investigation should not always be to arrive at the correct answer or to have the most accurate results but rather to have actively engaged in the investigative process itself.
Open-ended investigations provide opportunities for students to work in collaboration and cooperation with each other. This opportunity for shared thinking and questioning has been shown to promote deeper thinking and helps to instill in the students a passion for life long learning (Black and Williams, 2001).
Despite the many benefits of open-ended practical investigations many teachers may be reluctant to engage their students in this type of practical work. This is primarily due to the increase in time and resources required for students to plan and conduct the activity. Additionally, some students may be reluctant to participate in open-ended practical investigations as they lack the planning skills and confidence required to design their own experiment (Venville and Dawson, 2004). In these situations teachers need to provide students with the appropriate support and scaffolding to guide them through this process.
This open-ended practical investigation that I have developed is one that could be implemented with year 7 students. The Australian National Curriculum states that at this level students should learn “Mixtures, including solutions, contain a combination of pure substances that can be separated using a range of techniques” (ACARA, 2012).
The practical investigation would be done toward the end of a teaching sequence on ‘particle theory’. The students should be provided with adequate background knowledge of particles and the means by which they can be separated. These methods include solubility, magnetism, buoyancy and particle size.
At this year level, teachers should go over a number of lab safety procedures and rules to ensure that all students are aware of the expectations before they commence their investigation.
As can be seen in the image, there are generally 5 Stages to an effective open-ended practical investigation.
1. Set the Challenge: This can be done by either the student or the teacher
2. Provide the Materials: Students can be limited to specific materials or provided with whatever they deem necessary.
3. Encourage Exploration: This is where students collaborate to discuss their ideas and decide on a plan for their investigation
4. Share Ideas: The teacher should allow class time for students to share their investigation with the rest of the class
5. Connect and Reflect: Provide opportunities for students to reflect on their investigation, relate their investigation to 'real' world scenarios and to look up the answers to any questions they may have as a result of engaging in the task.
Image from Science Museum UK.
sm_student_handout.docx | |
File Size: | 98 kb |
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smrubric.docx | |
File Size: | 121 kb |
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References:
ACARA (2012). The Australian Curriculum v3.0 Science: Foundations to Year 10 Curriculum. Australian Curriculum, Assessment and Reporting Authority. Accessed 08/10/2012. http://www.australiancurriculum.edu.au/Science/Curriculum/F-10
Black, P & William, D (2001) Inside the black box: raising standards through classroom assessment. Paper presented at BERA Conference Nov 6 2001 (Longer version in Phi Delta Kappan Vol. 80 (2) pp.139-148 October 1998).
Lock, R. (1990). Open-ended, problem solving investigations. What do we mean and how can we use them? SSR, March 1990. Vol 71 (256).p63-72.
Venville, G and Dawson, V. (2004). The Art of Teaching Science. Crows Nest: Sydney. Allen and Unwin.