The answer is simply...no.

The primary focus on language instruction for the lower ESL levels should concentrate on building a vocabulary, meaning, and pronunciation; then grammar; then in higher levels and ABE instruction does proper spelling become more important. Many low-level ESL learners are illiterate in their own language, so concentrating on spelling in a second language is going to be a significant and time consuming challenge. Their concern will be acquiring "survival-level" language skills to navigate the institutions of their community and meet other family needs.

Actually, spelling is not much a factor in one's early stages of language learning. Of course, a learner will need a rudimentary foundation of the written word for acquiring reading and writing skills, but understanding and comprehension can be accomplished without accurate spelling. As long as the reader has a fundamental knowledge of the sounds of various word combinations and has an appropriate vocabulary, a reader can comprehend inaccurately spelled writing as demonstrated here:

Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it dseno't mtaetr waht oerdr the ltteres in a wrod are, the olny iproamtnt tihng is taht the frsit and lsat ltteer be in the rghit pclae. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.