CHAPTER ONE
INTRODUCTION
1.1 Background of the Study
Models can be used to facilitate learning especially where real objects may not serve the purpose. In explaining model, Macdonal (1991) sees model as a plan, a design, a preliminary solid representation to be followed in construction, something to be copied. Nachimias and Nachimias (1992) sees model as a likeness of something and a representation of reality. In other words, model depicts the actual representation of the original. It also explains how and why a particular phenomenon comes about. Ezeh (2006) stated that, a model is thus a simplified structuring of reality which presents-supposedly significant figures or relationships in a generalized form. Ezeh further stated that all models have basic identities in terms of characters and functions, and that model is dynamic. They are modified with time, in line with researches and developments in various fields. Haggett, Cliff and Frey (1977) in Ezeh (2006) classified models into conceptual and hardwares. Conceptual model have high degree of abstraction and are said to be “symbolic or theoretical” while hardware model (physical or empirical constructions) which depict the actual representation of the original is said to have low-level of abstraction and are often called “operational”. This research work adopted the hardware model which is regarded according to Nachimias and Nachimias (1992) as a likeness of something and a representation of reality. A model can be constructed and used in teaching some specific automobile parts such as crankshaft, piston, cylinder block, cylinder head, connecting rods, push rods, camshaft, plugs, valves, etc. A model is simpler in construction, easy to carry and move about because it is not heavy as in the case of a real auto-engine.
