CHAPTER ONE

INTRODUCTION

1.1     Background of the Study

Science and Technology have become the major ingredients of economic and  national advancement .Science and Technology influence every aspect of our lives. They are centrals to our welfare as individuals and society at large. The position and prestige of a Nation in world politics depends on the extent to which the country advances in science and technology. Omosewo (2006) defines Science as an activity which results into a testable, falsifiable and veritable body of knowledge. It accelerates the pace of change in the world by providing the foundation for wealth and development and brings improvement to the quality of life.

A scientist seeks to study in a systematic way the nature of things and the reason for the everyday changes. For instance, a scientist seeks to answer question of this kind; What is water? What does it contain? Where does it come from? Why, do we drink it? Can one make it? In what ways can it be used for the benefit of mankind? All these questions and many more of their kind face the scientist when he come across a new substance or when he observes a new change in nature.

Chemistry as one of the basic natural science subjects plays a vital role in advancement of science and technology. Today chemistry has two sides; on one hand, it provides the basis for our current world picture, while on the other hand it is the foundation of other subjects for technological developments. Of the three science courses; Biology, Chemistry and Chemistry, chemistry holds the strongest position as a major subject prerequisite into career in science and technology (Esiobu,2007).

Our civilization today is the direct result of the work of scientist. The important reason why we study chemistry is that it play part supplying our basic need; The food we eat that is needed for warmth and energy repair of tissue, for growth and for resistance diseases. The alcohol we drink is made by fermentation of sugar starchy materials. The cloth we wear are made from plant and animal fibres and also from synthetic fibres discovered by chemist. Drugs use in medicine is produced by chemist it also provides a bond background for the future specialization.

The study of chemistry in the senior secondary schools is no more a mere make-up of number of subject for examination purposes (Bajah 1991). Chemistry generally studied the everyday uses and that justified its inclusion in the syllabus and curriculum of secondary schools.

The nature of chemistry makes it different from any other subject. Between the ages of 14 and. 16 years, students who have opted to study chemistry spend some 300 hours or more learning chemistry in school, and no doubt an additional amount of time at home warning the subject. What do they achieve for this expenditure of time and effort? The answer would seem to be very little as available (Oderinde, 1977). When then does the problem lie? Is the chemistry attempt to teach too difficult for students of this age range or is external examination they sit for too difficult? Does it require reasoning skills that are beyond the developmental level of most of students? This situation calls for an urgent attention and improvement especially now that there is a clamour for scientific and technological advancement in the country. Some will say that recent on curriculum matching suggests that this is so. On the other hand, others would suggest, that students commence the y of the subject with limiting factors, pre-conceptions and firmly entrenched misconceptions. These and many other reasons have adduced for possible high failure rate in chemistry. But the question still remains, "Has there been awareness on the part of the examination body that questions set for students may not match their intellectual capabilities.

Nigeria Education Research and Development council (NERDC,2003) central to the reason generated in the report is that cognitive functioning is formal operation stage according to piaget (NSSSP, 1999).

Cognitive development is the emergence of the ability to think and understand. Piaget believed that  the  development  of  a  child occurs through a continuous transformation of thought processes. A developmental stage consists of a period of  months  or  years  when  certain  development  takes place. Weinert & Helmke, (2007) are of the view that students are usually grouped by chronological age, their development levels may differ significantly, as well as the rate  at  which  individual  children  pass  through  each stage. This difference may depend on maturity, experience, culture, and the ability of the child (Papila &  Olds,  2008).  According   to  Berk  (2006),  Piaget believed  that  children  develop  steadily  and gradually throughout the varying stages and that the experiences in one stage form the foundations for movement to the next. All people pass through each stage before starting the next one; no one skips any stage. This implies older children, and even adults, who have not passed through later stages process information in ways that are characteristic of young children at the same developmental stage (Eggen & Kauchak, 2007).

Piaget identified four primary stages of cognitive development; these stages include sensorimotor, preoperational, concrete operational, and formal operational. At the formal operational stage which is from ages 12 or 13 till adulthood, the child is capable of forming hypotheses          and      deducing possible consequences, allowing  the child to construct  his own mathematics. Furthermore, the child typically begins to develop abstract  thought patterns where reasoning  is executed using pure symbols without the necessity of perceptive data. For example, the formal operational  learner can solve x + 2x = 9 without having to refer to a concrete situation presented by the teacher, such as, “Tony ate a certain number of candies. It is worthy of note that at this stage the child is able to develop a problem solving skill which can be used to solve problems in chemistry.

 According to Mayer and Wittrock, problem solving is “cognitive processing directed at achieving a goal when no solution method is obvious to the problem solver” (2006, p. 287). This definition consists of four parts: (1) problem solving is cognitive, that is, problem solving occurs within the problem solver's cognitive system and can only be inferred from the problem solver's behavior, (2) problem solving is a process, that is, problem solving involves applying cognitive processes to cognitive representations in the problem solver's cognitive system, (3) problem solving is directed, that is, problem solving is guided by the problem solver's goals, and (4) problem solving is personal, that is, problem solving depends on the knowledge and skill of the problem solver. In sum, problem solving is cognitive processing directed at transforming a problem from the given state to the goal state when the problem solver is not immediately aware of a solution method. For example, problem solving occurs when a high school student writes a convincing essay on the causes of the American Civil War, understands how the heart works from reading a biology textbook, or solves a complex arithmetic word problem.

Problem solving is ‘‘the process of moving from a situation in need of resolution to a solution, overcoming any obstacles along the way’’ (Sternberg & Williams, 2009). Often, it is assumed by instructors that problem-solving practice will, by itself, result in students developing expertise in problem solving and a good understanding of the concepts in the problems (Tsaparlis, 2009). This assumption is not warranted in chemistry instruction, however, because research indicates that many students are leaving their chemistry courses with inadequate problem-solving skills and a poor understanding of the concepts in the problems (Bodner, 2003; Teichert & Stacy, 2002). In response to students’ lack of expertise in problem solving, chemistry educators are calling for reform in the teaching and learning of chemistry problem solving because they would like all of their students to become, relatively speaking, ‘‘experts’’ in solving the problems posed in these courses (Cohen, 2006).

Models Of Problem Solving in Chemistry

One approach to understanding “what we do, when we don’t know what to do” has been to develop models that try to describe the generic steps or stages problem solvers go through (or should go through) as they struggle with a problem. In theory, if a good model of problem solving were available, we should be able to create an instructional strategy based on this model that would improve students’ problem-solving abilities. However, when we compare various models with what people do when they solve problems, it becomes clear that teaching problem solving isn’t this straight-forward.

Any description of problem solving is likely to oversimplify this complex and somewhat eclectic process. That is especially true of Polya’s model, which grew out of his work on relatively well-structured problems in mathematics. Polya’s (1946) popular model, consists of four steps: (1) understand the problem, (2) devise a plan, (3) carry out the plan, and (4) look back. For many years, researchers have used the following problem in seminars on problem solving to probe the validity of Polya’s model:

A sample of a compound of xenon and fluorine was confined in a bulb with a pressure of 24 torr. Hydrogen was added to the bulb until the pressure was 96 torr. Passage of an electric spark through the mixture produced Xe and HF. After the HF was removed by reaction with solid KOH, the final pressure of xenon and unreacted hydrogen in the bulb was 48 torr. What is the empirical formula of the xenon fluoride in the original sample? (Holtzclaw, Robinson, and Nebergall, 1984).

It is rare, indeed, to find a practicing chemist who truly “understands” this problem until he or she arrives at the answer, XeF2. Their behavior is more like the general, tentative steps outlined by Dewey (1910).

Lee and Fensham (1996) note that Dewey’s model of problem solving consists of five stages that might be described as follows: (1) A state of doubt or awareness of difficulty, (2) an attempt to identify the problem, (3) transforming problem-setting propositions into problem-solving propositions or hypotheses, (4) successive testing of hypotheses and reformulation of the problem as necessary, and (5) understanding the successful solution and applying it both to the problem at hand and other exemplars of the problem. The difference between Dewey’s model of problem solving and Polya’s can be related to the difference between a routine exercise, which is worked in much the way Polya suggested, and a novel problem, which is best addressed via general models similar to the one outlined by Dewey.

Researchers have used the following model of problem solving developed by Wheatley (1984) to teach chemistry (Bodner & Pardue, 1995). The model are as follows;

• Read the problem
• Now read the problem again
• Write down what you hope is the relevant information.
• Draw a picture, make a list, or write an equation or formula to help you begin to understand the problem.
• Try something.
• Try something else.
• See where this gets you.
• Read the problem again.
• Try something else.
• See where this gets you.
• Test intermediate results to see whether you are making any progress toward an answer.
• Read the problem again.
• When appropriate, strike your forehead and say, “son of a ...”.
• Write down an answer (not necessarily the answer).
• Test the answer to see if it makes sense.
• Start over if you have to, celebrate if you don't.

Whereas exercises are worked in a linear, forward-chaining, rational manner, this model of problem solving is cyclic, reflective, and might appear irrational because it differs from the approach a subject matter expert would take to the task. One limitation of Polya’s model is the assumption that we begin by “understanding the problem.” The models proposed by Dewey and Wheatley presume that “understanding the problem” arises toward the end of the problem-solving process.

Analysis of transcripts of problem solving protocols elicited from 10 teachers and 33 Grade

12 students led Lee and Fen sham (1996) to identify seven distinguishable processes in problem solving: (1) Reading and comprehending the problem statement as a whole, rephrasing or simplifying the problem statements, using symbols or diagrams to visualize the problem so that they could understand it, (2) translating the parts of the problem statement into statements that had meaning to themselves, (3) setting goals or sub goals, (4) selecting what they recognized as important information from the translation statements obtained in the first three processes, (5) retrieving rules or facts from memory, (6) achieving goals and or subgoals by explicit or implicit linking of processes 4 and 5, and (7) checking the paths of the solution or the answers. Lee and Fensham’s results are more consistent with either Dewey’s or Wheatley’s model of problem solving than they are with the model proposed by Polya or one of the other stage models based on Polya’s work.

All of these models of problem solving have merit, but problem solving is a complex process that is affected by many variables. No single model — not even the collection of models outlined here — captures all nuances of problem solving. Additional insights are provided by research that contrasts the problem solving behavior of “experts” and “novices.”

Relationship between Cognitive development and Problem Solving Skills

Historically, learning science and teaching it to all students at the school stage has been motivated by the belief that a study of science subjects such as chemistry, mathematics, chemistry, etc. helps students to learn to reason and apply such reasoning to everyday problems. It is believed that learning science leads to learners’ cognitive development. Thus, one of the important questions that all educators must constantly ask themselves is: Does the chemistry that we teach (and that our students learn) lead to development of students’ cognitive abilities?

This leads to deeper understanding that must enable students to look at and understand a new situation, delve into the repertoire of chemistry knowledge that they have in terms of concepts, processes, and ideas and adapt or modify those ideas so as to apply them towards resolving a new problem situation. Such understanding calls for building deep connections between concepts, a variety of lenses and representations with which to view the concepts, and flexibility that allows one to sufficiently modify concepts so as to apply them to a new situation. It requires students to develop a rich network of ideas that one may draw from when faced with a novel situation. In this process, students develop habits of the mind that enable them to analyze other situations that they may encounter in life, mathematical or otherwise. This critical blend of processes is what educators refer to as problem solving. It is this kind of cognitive development that most modern societies would like their citizens to develop.

Problem solving, as used in mathematics education literature, refers to the process wherein students encounter a problem – a question for which they have no immediately apparent resolution, nor an algorithm that they can directly apply to get an answer (Schoenfeld, 1992). They must then read the problem carefully, analyze it for whatever information it has, and examine their own mathematical knowledge to see if they can come up with a strategy that will help them find a solution. The process forces the reorganization of existing ideas and the emergence of new ones as students work on problems with the help of a teacher who acts as a facilitator by asking questions that help students to review their knowledge and construct new connections.

1.2       Statement of the Problems

Problem solving skills are a prime concern to educators because of the immense benefits good problem solvers reap. Although most educators are well aware of these benefits, probably the greatest benefit is the independence acquired on the part of the learner. The learner gains a sense of accomplishment from finding a solution to using his own volition.

Despite the interest manifested by teachers in cultivating in their students problem solving skills, personal classroom experiences with senior secondary school students in Nigeria has shown that most learner are yet to acquired critical thinking and formal operational thought which are not automatically acquired but need to be taught, required for success in chemistry and related discipline. Age has to do with cognitive functioning, it cannot be compromised, most learners are very immature and their ability are below what chemistry required expect some genius among them (Eh.kind, 1962), (hovel, 1961). This can be attributed to non-attainment of formal operational stage-the stage at which student can think in abstraction and logically too .unless, these deficiencies are rectified student will continue to have poor problem solving skills.

1.3       Purpose of the Study

The main purpose of this study is to;

1. Assess cognitive development levels of chemistry students.
2. Assess the problem solving skills of chemistry students.
3. Examine the relationship between cognitive development levels of chemistry and their problem solving skills.

1.4       Research Questions

The following research questions will be examined in the course of this research work.

1.         What are the cognitive development levels of chemistry students?

2.         What are the problem solving skills of chemistry students?

3.         What is the relationship between cognitive development levels and problems of solving skills of chemistry students?

1.5       Research hypothesis:

H01:      There is no significant relationship between students’ cognitive development levels and their problem solving skills in chemistry.

H02:        There is no significant difference between male and female chemistry students in their cognitive development levels and problem solving skills

1.6. Significance of the study

The findings of the study will be beneficial to the following;

• It will help Chemistry teachers on how to encourage and motivate their students on how they can develop their problem solving skills.
• it will also help students especially chemistry students on how they can apply the problem solving skills in their learning situation.
• it will be useful for researchers in their further research in this field.

1.6       Scope of the Study

This study will be limited to selected secondary schools in Mainland Local Government Area in Lagos State.