Yoruba, a language of the Kwa group of the Niger-Congo family is spoken along the West African coast in such countries including Nigeria, the Republic of Benin, Sierra-Leone, and Togo. It is used for religious purposes in places like Brazil and Cuba. It is spoken by about 25 percent of the Nigerian population. Yoruba language has been classified into three major dialect groups: the Central Yoruba; the Northwest Yoruba; and the Southeast Yoruba. The Northwest Yoruba, designated as the Standard Yoruba, will be the subject of study in this paper.This proposal seeks to examine pedagogical implications of vowel lengthening to learners of Standard Yoruba as a second language. Vowel lengthening in Standard Yoruba can be described to be a product of two interacting phonological processes: consonant deletion and vowel assimilation. These processes can be lexically or syntactically conditioned. Second language learners of Yoruba can be faced not only with problems of unfamiliar tones but also of vowel contiguity that can result in vowel lengthening or vowel deletion. This paper seeks to help such learners recognize instances where vowels lengthen as opposed to where they delete, and as such can avoid confusion or ambiguity.