This paper discussed the functions, essence, and applications of educational evaluation in the teaching-learning processes; in primary schools. It outlined the definitions of evaluation, the stepwise diagram of an evaluation process, succinct explanation of the types of evaluation, and its essence and the steps in educational evaluation. Also, reflection and thoughts centered around the functions, essence, and how educational evaluation is applicable in improving and sustaining a robust teaching and learning strategy in primary schools. More so, the paper concluded that primary school teachers as well as learners; need regular evaluation and evaluation reports, for effective and efficient teaching-learning transactions. For the learners, educational evaluation increases their learning motivation, development of good study habits, feedback, and necessary corrective measures. Teachers require evaluation results to monitor the effectiveness of instruction as well as the instructional materials, choosing learning experiences, diagnosing learners learning difficulties in order to improve the instructional process. Accordingly, it was recommended that educational evaluation practices, strategies, and enlightenment be boosted among all primary school stakeholders.