Utilizing Laboratory Activities and Dialogue as Hands-on and Minds-on Instructional Strategies

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Abstract.

This paper attempted to stimulate science teachers to the need to overcome the obstacle posed to the use of laboratory instructional strategies by the absence of school science laboratory.

It demonstrated how to use laboratory activities and dialogue as hands-on and minds-on strategies to teach the concept of Force and its subordinate concepts at the primary school level.

It equally examined the concept of Force and provided useful hints on how to improvise a spring balance. The paper advocated for the provision of primary science laboratory in all primary schools, for sustainable development in science education, in Nigeria.

Introduction.

Science is a vital pillar of the current civilization epoch hence, its inclusion in the school curriculum at all levels of the educational ladder is not astounding. It is essential to equip children with a sound foundation in science to contribute meaningfully to its development.

This requires meaningful learning of the products, process and ethics of science in an integrated manner. Hence, teachers have to engage pupils actively in the learning process through the use of Pupil-Centre Approach to teaching. There are several instructional techniques and strategies based on this approach that can be employed to ensure meaningful learning of scientific knowledge, process skills and ethics in an integrated manner.

The root of the Laboratory instructional technique is in Learner-Centred Approach to teaching. It is also an integral component of school science. Simple laboratory activities and various forms of dialogues can be used as Hands-on and Minds-on Instructional Strategies respectively. Hands-on and Minds-on Instructional Strategies is based on learn-by-doing approach in which students actively engage their natural curiosity in learning.(Barbara, 2012). Turner (15-April-2007) noted “An increase in the use of hands-on and minds-on' learning can significantly increase the degree to which students become active learners in the classroom.”

The focus of this paper is to demonstrate how laboratory activities and dialogue can be used s to teach the concept of force as Hands-on and Minds-on Instructional Strategies. Children naturally have intrinsic interest in exploring their environment as part of efforts to gain useful insight into the world around them.

This attribute is akin to that of scientists hence, engaging pupils in ordinary exploratory activities based on science process skills could significantly facilitate meaningful learning of basic concepts in science such as Force. It is not enough for pupils to develop scientific process skills only, they equally need to acquire appropriate theoretical knowledge and ethics of science in other to have an in-depth understanding of science related concepts, and phenomena, herein lies the usefulness of dialogue(discussion) instructional strategies. Indeed dialogue is a potent strategy for developing their intellectual skills. Laboratory Instructional Activities.

The laboratory is an organizational setting where science students observe and manipulate materials associated with scientific concepts learnt through textbooks, lectures and discussions. This traditional view means that laboratory works are merely for verification of topics already learnt in the class. Hence, students were forced to accept conclusions of existing laws, theories, etc.

Students do not experiment, they only verify. For instance, students taught the law of conservation of mass will enter the laboratory to work only to reach the stated law. This must not be allowed to prevail in school science laboratory work. Students should be made to carry out experiment. They must be provided with materials for experiment and procedure to follow. It should be noted that not all laboratory activities can be called experiments.

Experiments are activities on procedures designed for testing hypotheses, confirming what is already known and discovering what is unknown (Abdullahi 1982). As rightly observed by Sowege and Jegede (2002), some science concepts may not lend themselves to experimental procedures. Careful observations, measurements and other similar process skills are sufficient to gain a basic understanding of such concepts. This is particularly the case for many basic science concepts taught at primary and secondary school levels.

Laboratory activities do not only stimulate pupils’ interest in science by keeping them actively involved in the learning process it equally re-enforce what they learnt during theory class as noted by Omosewo(2001) Laboratory activities can be structured or unstructured according to Sowege and Jegede (2002). Structured activities provide pupils relevant guidelines for the conduct of activities designed to arrive at a predetermined result. Whereas in unstructured activities pupils are to solve a given problem using their own designed procedure. They have to collect and analyze data and arrive at their own conclusion.

It is pertinent to state that laboratory activities can also be an admixture of structured and unstructured procedure. This procedure is particularly relevant at primary and lower secondary school levels where pupils are just gaining rudimentary skills in scientific investigations. The absence of primary science laboratory in most public primary schools, in the nation, is a significant challenge to successful utilization of the laboratory based instructional strategies.

However, the fact that many science based activities can be carried out within the classroom as well as the immediate school environment should catalyze science teachers to design instructional strategies involving basic science based activities whenever the need arise.

The laboratory activities described in this paper can be carried in regular classrooms and school environment in a situation where there is no science laboratory. The materials for conducting the activities are also readily within the reach of teachers and pupils in public and private primary schools. The activities are design to achieve the objectives listed below.

(a) Provide hands-on experiences for the pupils through the development of manipulative skills necessary to conduct scientific investigations on the concept of force.

(b) Develop cognitive ability such as, problem solving skills, critical, logical and analytical thinking skills, and ability to make a generalization.

(c) Develop appropriate scientific ethics such as curiosity, objectivity and honesty, among

(d) Appreciate scientific processes skills and sprit.

(e) Develop communication ability, accurate observation, and description.

(f) (f) Clarify theoretical discussions on the concept of force to enhance meaningful learning.

(g) (e) Provide experiences that will make the concept of force verifiable.

Dialogue.

Dialogue is simply a formal discussion or negotiation between opposing views. In a classroom situation, dialogue is an instructional strategy that helps to develop the pupils’ intellectual skills. Dialogue in its various forms is an essential ingredient in concept clarification strategies. It is indeed a highly potent minds-on instructional strategy. A pupil can engage in dialogue with self through thinking reflectively on a topic or partial dialogue by listening to other people such as in reading and listening to a lecture.

The most active and dynamic dialogue situation is when a teacher organizes pupils into small discussion groups or dialogue with professionals on a topic, (Dee Fink, 1999). There is no doubt that learners at every level can participate in the various forms of dialogue when provided the enabling environment. Live dialogue with other people is interactive, dynamic and keeps pupils actively at the centre of teaching and learning process.

However, teachers need to be sensitive to time and class management problems that may arise when engaging pupils in live dialogue with other people especially professionals/experts. It is equally valuable to be sensitive to the possible introduction of new misconceptions or the re-enforcement of existing misconceptions (related to the concept under focus) held by pupils in their cognitive structures.

Concept of Force.

In a clear sense, force can be conceived as the Pull or Push exerted on an object in a direction. It is any action or influences that accelerate objects (Microsoft2007).Force do change the state of motion of an object by increasing or decreasing the velocity of the object. Motion refers to the act of moving hence, any object that is moving is said to be in a state of motion. Whereas velocity has to do with the speed at which an object is moving in a direction.

It is the rate of change in position of an object as the object is moving in a direction. An object will continue to move at a constant speed in a straight line unless another force acts upon the object. There are two main types of force namely, (a) Contact force, such as push, pull tension and friction and (b). Force fields. (Ron,K.2007).

Contact force refers to forces whose sources are in contact with the object to which they are applied. For instance, if you push down a book on the table with your hand, the force exerted on the book by pushing it is in direct contact with the book.

Similarly if you use your hand to pull towards you a whopping stone through a rope attached to it, the Force exerted on the stone through pulling is in direct contact with the stone. Examples of force fields include Gravitational Force, Magnetic Force as well as Electrical Force. Force make objects to either cause increase or decrease or change in the direction of motion of an object. Forces always occur in pairs; hence change of motion is due to unbalanced force. Whenever an object is at rest, it means that forces exerted upon the object are equal and opposite. In a situation where the force are unbalance, the object would move towards the unbalanced force.

For instance, a book on top of a table is at rest hence all force acting upon it from all directions are equal. However if you exert force on it by pushing it towards a direction, the force acting upon it will become unbalanced. Hence the book will move towards the direction of the unbalanced force. Force have both magnitude and direction hence it is a vector. Whenever many force acted upon an object, the force can be combined to give a net force. (Bello,2005). When the net force is equal to zero / balanced the object will either be at constant velocity or in a state of rest. The unit of measurement for force is Newton.

Concept of Friction.

Friction can be conceived as the Force that opposes motion. It usually acts parallel to the surface on which the motion occurs. Therefore, there is a general tendency for an object in motion to slow down and come to rest due to Friction. Indeed before an object can be in a state of motion, Friction has to be overcome. Friction continues to oppose the motion of an object as long as the object continues to move.

Friction slows down object in motion until it eventually stops moving. This is the time when the Friction disappears, only to be set up once the object starts moving again.. Friction can occur in any medium, it can be between two solids in direct contact, or between solid object moving in liquid medium or gas medium. Friction between two solid objects or solid and liquid is usually greater than between solid and air. Friction is greater between rough surfaces than in smooth surface. Friction is responsible for wear and tire of parts of machines.

In all forms of machine, energy has to be used to overcome Friction to keep the machine in motion. Such energy is converted to heat and sometime sound energy. This results in heating up of the machine and wear and tire of the machine parts. Therefore, applying oil and grease to machine reduces Friction between parts in contact with each other. Oil and grease are lubricants that help to reduce Friction.

Friction is not totally a negative force. It is also immensely useful, for instance it is the Friction between the rough surface of car tire and the road rough surface that enables the tire to grip on the road to move the car. It is equally the Friction in the brake system of cars (and other Automobile) that enable us to stop the car. Similarly without Friction between sleeper / foot and the ground surface, walking about will be extremely difficult if not impossible.

This readily comes to mind if you had ever worked on a sheer smooth/polished surface or wet, slippery surface. Friction is also put into use in safety matches; usually the head can be ignited only by striking on the rough surface on the match box, which contains powdered glass (to set up Friction), Chemicals, and Glue. When the match is struck, the heat generated by the Friction set up, ignites the chemical substances and the head of the match burns, producing flame. (Bello,2005)

Integrating Laboratory Activities and Dialogue Instructional Strategies to Teach the Concept of Force.

The concept of force and its subordinate concepts is abstract in nature. It also, has different meanings outside the field of sciences. Consequently it is essential to commence instruction with concept clarification activities to eliminate semantic misconceptions in the pupils’ cognitive structures. This can be carried out in the following steps:- (a) Identify the pupils’ preconceptions of Force by asking them to think reflectively on the concept.

This should be a dialogue with self at this stage. (b) Identify the pupils' misconceptions and alternative conceptions related to the concept of Force. (c) Present the identified misconceptions and alternative conceptions to the pupils. (d) Engage pupils in a dynamic dialogue on their misconceptions and alternative conceptions. The focus here should be on negotiation between opposing views, and (e) Presenting the appropriate scientific conception of Force In a summary form. Note that this is a partial form of dialogue.

The following elementary science based activities on the concept of force should now be carried out by pupils either in small groups or individually. The materials needed for the activities include; rope/twine, wood block/stone, standard spring balance / improvised spring balance, lubricants (grease//soap solution/Vaseline), smooth surfaces(glass sheet ), magnetic bars, nails/pins/needles, torch light battery, lamp, wire, rough surfaces (floor) and ball bearings.

Class Activities on the Concept of Force.

Direct and guide pupils to carry out the following activities on the concept of Force.

1. Direct pupils to set a wood /stone in motion on a (i) rough surface, and (iii) smooth surface

2. Direct pupils to tie a rope/twine to the wood/stone and use it set the wood/stone in motion

3. Direct the pupils to state their observations on the two activities. Teacher should later engage pupils in dialogue to clarify the concept of Force using the Pushing and Pulling activities.

4. 4.Guide pupils to place a magnetic bar close to a nail/pin/needle, observe and describe the action of magnet on the nail.

5. Direct pupils to throw small stone(s) up and explain their observation their observation

6. Guide pupils to construct a basic electric circuit and ask pupils to explain the source of the light produced by the circuit.

7. Engage pupils in dialogue with self by asking them to reflect on what they learnt about the concept of Force based on the activities carried out so far.

8. Organize pupils into small groups for active dialogue on the concept of force based on what they learnt during the activities

9. Reconcile pupils’ conceptions of force with the appropriate scientific conceptions of force and its sub ordinate concepts. Distinguish between the various forms of Force(Contact force - push, pull, tension and friction; Field force-magnetic, gravitational and electrical force.)

10. Guide pupils to use spring balance to move wood blocks /stones of different sizes and determine the force applied to initiate the movement.

Class Activities on the Concept of Friction.

Direct and guide pupils to carry out the following activities to help the pupils to develop appropriate conception of the concept of friction.

a. Attach a spring balance to a 100g wood block / stone and place it on a sheet of glass.

b. Carefully pull the spring balance gradually and record the reading on the balance just when the wood block / stone begin to move at a steady speed.

c. Repeat the above exercise, on top of a table.

d. Wet the surface, of the glass and table with soapy water and repeat the exercise.

e. Repeat the exercise on a cement floor surface.

f. Observe the surfaces of the stone, glass, wood block, cement floor, table and sheet of glass using a powerful hand lens or microscope. .

g. Rub their palm surfaces together vigorously and record their observation.

h. Analyze data gathered in the activities carefully.

At the end of the activities pupils should be guided to engage in active dialogue on their results / observations, while the teacher should present the scientific conception of the concept of friction to the pupils.

Conclusion and Recommendations.

The laboratory is an integral component of modern science hence, engaging pupils in laboratory activities is essential for meaningful acquisition of scientific knowledge, processes and ethics. It is therefore, desirable that every primary school in the nation should be provided with fully equipped science laboratory. Science is concern with the environment hence; school science should go beyond laboratory activities. Scientific investigations often take place outside the laboratory. This is a key indication that science teaching and scientific activities by pupils and teachers should not be limited to the laboratory alone. The challenge before science teachers is to design appropriate scientific activities that can be carried out by pupils with or without school science laboratory. Science teachers must always improvise simple, basic laboratory materials for effective use of hands-on strategies, in the absence of such materials.

References.

Abdullahi, A (1982). Science teaching in Nigeria. Ilorin: Atoto press.

Barbara, J. (2012). Capturing Joy: “K-12, I Do Science”. Retrieved from researchfrontiers.uark.edu , on 2nd May,2012.

Bello,G.(2005). RSSEK Teacher Training: Integrated Science. Lagos: Inform-Ed Consultants

Dee Flink, L. (1999) Active Learning. Retrieved from honolulu.hawaii.edu.htm on 2nd April,2007.

Microsoft Incorporation (2007).Student with Encarta Premium 2007. New York: Author.

Omosewo, E.O (2001). Laboratory, Demonstration and Field Trip Methods of instruction. In I.O.Abimbola (Ed). Fundamental Principles and Practice of Instruction. Ilorin: Department of Curriculum Studies and Educational Technology, University of Ilorin.

Ron,K(2007).Force affect motion. Retrieved from school-for-champions.com/science/force_motion.htm. on 2nd may,2012.

Soweje, R.O.and Jegede, S.A.(2002). Science Education and Science Teaching Methods. Ado-Ekiti: Greenline Publishers.

Turner, R.C (15-April-2007) Hands-on and minds-on approach to school science Medical Science News (Sunday, 15-Apr-2007). Retrieved from news-medical.net.htm., on 14th May, 2007.

Appendix I:Improvised Spring Balance

Materials : Empty tin, Spiral spring / Rubber strip, Paper, Scissors, Gum and Metal rod (small size).

Procedure:

• Make a small hole at the bottom of the tin and another hole at each side of the open end of the tin.

• Make a long narrow cut (slit) on one side of the tin to cover at least three-quarter of the length of the tin.

• Pass the upright end of a J- shape metal rod through the hole at the bottom of the tin and attach the spring / rubber to the rod.

• Attach a small rod (to serve as an indicator) to the spring / rubber towards its free end.

• Pass another metal rod through the holes at the side the tin.

• Adjust the indicator to project its free end out through the slit.

• Cover the open end of the tin with its lid or any suitable material.

• Tightly fix a strip, of paper to the side of the slit and calibrate it ( mark scale on the paper ).

BY

BELLO, GANIYU (PhD)

School of Sciences,

Kwara State College of Education Ilorin, Nigeria.


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