An area that brings problem continuously to second language (L2) learners of English is vocabulary development. Exposing words to students in isolation or in wrong context(s) causes L2 learners of English to lack working vocabularies. This study investigated the effects of exposure to context clues on vocabulary development of Junior Secondary II students in Zaria Education Zone, Kaduna State. Most students at this level merely memorise vocabularies in isolation without knowing how to put them in proper contexts. This necessitates addressing the problem. Some of the questions the study answered were, to what extent does the exposure to context clues support students in vocabulary development in an appropriate context at J.S II. What types of context clues will be appropriate in developing student's vocabulary in an appropriate context at J.S. II? The research employed quasi-experimental design. Cluster sampling was applied in the sampling. Vocabulary achievement test was the instrument used in collecting the data. Ttest was applied in testing the hypotheses. The study found that students taught with context clues have significant higher performance than those taught with traditional method in vocabulary development. Then significant differences exist in various types of context clues where visual context clue was ranked first while summary context clue was less effective than others on vocabulary development in context. The study recommended that, in vocabulary development, words should be presented not in isolation but in context. Secondly, teachers should provide various learning contexts since a single word can generate different meanings, depending on the context of its use