INTRODUCTION 
1. BACKGROUND OF STUDY

Qualitative education remains the fulcrum for global development and freedom. Therefore all hands must be on deck worldwide to formulate policies that will enhance qualitative education right from elementary school to tertiary institution, and continuous, effective monitoring must be well established to check all factors that may frustrate this global pursuit. Hence, most societies require children to attend school for a specified number of years or until they reach a certain age. Many of the benefits of schooling occur in part because students learn some new knowledge or skills that enhance their ability to communicate, solve problems, and make decisions.

Academic achievement of students especially at the secondary school level is not only a pointer to the effectiveness or otherwise of schools but a major determinant of the future of youths in particular and the nation in general. The medium through which the attainment of individuals and the nation’s educational goals can be achieved is learning. Learning outcomes have become a phenomenon of interest to all
and this account for the reason why scholars have been working hard to unravel factors that militate against good academic performance (Aremu & Sokan, 2002). This phenomenon has been variedly referred to in literature as academic achievement, or scholastic functioning. Academic achievement of learners has attracted attention of scholars, parents, policy makers and planners.
In an attempt to put sound education on ground worldwide, many factors have been incriminated as being responsible for falling standard of education where it is perceived and established. Among such factors is the issues of ‘’class size’’ .Adeyemi (2008) defined class size as an educational tool that can be described as an average number of students per class in a school, while Hoffman (1980) described it as the number of students per teacher in a class. Kedney (1989) described it as a tool that can be used to measure performance of the education system. A lot of argument has gone on the impact of class size on performance, some fingering over-bloated class size as the main factor responsible for falling standard of education, most especially in the elementary or secondary level of education in Nigeria, however others see this as mere coincidence seeing other factors as being responsible.

Class size is an important factor with respect to academic performance of students. There is a consensus among researchers and educational scholars that, student’s achievement decreases as class size increases. The effect of class- size on cognitive achievement has been debated and researched for many years, this has been inconclusive. Class size refers to educational tools that can be used to describe the average number of students per class in a school. In emphasizing the importance of class-size to the learning teaching process, ALL Nigerian Conference of Principals of Secondary Schools (ANCOPSS) recommended a maximum of forty students per class for efficient and effective teaching.

STATEMENT OF PROBLEM
Schooling has multiple purposes, for instance, higher levels of schooling are associated with higher earnings and economic mobility, better health, lower mortality rates, and greater participation in the leadership process in one’s immediate and the global community. In an attempt to put sound education on ground worldwide, many factors have been incriminated as being responsible for falling standard of education where it is perceived and established. Among such factors is the issue of classroom size. Fabunmi,BraiAbu and Adeniyi (2007) pointed out that classroom congestion and low utilization rate of classrooms are common features of secondary schools in Nigeria. They have negative impact on both secondary school teacher productivity, student learning input and thus secondary school student academic performance.In particular, poor scholastic achievement can influence the reputation of a school because academic success is associated with the quality of the school. The alarming rate of failure in our secondary schools is highly embarrassing.
In view of the points above, the study focuses on classroom size as it correlates with academic performance of secondary school students in Nigeria
1.3 OBJECTIVES OF THE STUDY
The main aim of the study is to influence of classroom size on academic performance of secondary school students in Nigeria. Specific objectives of the study include:

1.4 RESEARCH QUESTIONS                                             
                           
For the purpose of this research work the following research questions have been formulated;                                                
1. What relationship exists between class-size and the quality of output from secondary schools in Nigeria?
2. Is there any significant difference between the quality of output of students in schools having an average small class-sizes and the quality of output of students in schools having an average class-sizes in Nigeria?
3. What are the general attitudes and preferences of students in secondary schools regarding class size?
4. Is there significant scientific evidence to prove and convince legislators, school educators, parents and other major stake holders in the educational fraternity that class size makes a difference in student academic performance.

1.5 RESEARCH HYPOTHESES             
                                       
The following hypotheses will be tested to guide this study;  

1.6 SIGNIFICANCE OF THE STUDY
This study will be highly important to the government at all level, the parents, educational planners, decision and policy makers as well as other stakeholders in education. However, this study will help the public and private schools to know and ascertain the influence of class size on the students’ academic achievement, thereby making the stakeholders to develop appropriate strategies in solving the classroom overcrowding in the school and as well enhance the students academic performance.
The study will provide an insight understanding for the public and private schools to know the effect of Classroom size on the students’ academic achievement, thereby making the school stakeholders to develop appropriate measures of improving the school environment for the students in the schools.
Through this study, the students as well as the teachers will be able to know the effect of class size on the student’s academic achievement.
The class size as relates towards students academic achievement will enable the government and the general public to be aware of the effects of these factors and work towards better improvement.
It is important to note that findings in this study will also serve as a source of reference for other researchers who may want to conduct the same or similar study in other subjects or part of the country.
1.8 LIMITATIONS OF STUDY

1.9 DEFINITION OF TERMS
Achievement
According to Black and William (1998:219) achievement is past oriented. It is based on a specific body of knowledge and it reveals areas of weakness, which can result in remedial action. Achievement can also reveal competence and such results can be used to predict future performance.

Academic Performance
This refers to the students’ achievement, scores within the class and his position relative to all those subjected the same test.