FAIR is a non-profit organization dedicated to providing well-documented answers to criticisms of the doctrine, practice, and history of The Church of Jesus Christ of Latter-day Saints.
Pergunta: Será que a Igreja ensina ou acreditam que Joseph Smith era "analfabeto"?
Question: Does the Church teach or believe that Joseph Smith was "illiterate"?
The Church teaches that Joseph was uneducated, not "illiterate"
One website that is critical of the Church makes the following claim about Joseph Smith's education:
This wasn't a family of illiterates. Education was important to the Smith family, and although Joseph may have only had limited formal education in a typical classroom, his parents undoubtedly schooled him at home. Also Joseph was going to high school when he was 20 years old in Harmony PA with the Stowell children.
Even today many people home-school their children. Would anyone say that these home-schooled children are uneducated? It's true that they do not have a formal education but for the most part, home-schooled children have similar, and in some cases superior, education than traditionally-schooled children. 
The fact that Joseph could read the Bible demonstrates that he was not illiterate
The Church never taught that Joseph Smith was "illiterate." The official account of the First Vision refutes this, since it demonstrates that Joseph was fully capable of reading and understanding the Bible. The statement from the critics that Joseph's family "wasn't a family of illiterates" argues against a point that is never being made.
More to the point, equating Joseph Smith's "home schooling" to 21st-century home schooling is a false comparison. It was Joseph himself that said in his 1832 history that he was "deprived of the benefit of an education." One must ask the question: Why did Joseph's contemporaries not think him capable of producing the Book of Mormon? 21st century "homeschooling" has nothing to do with education on the frontier of 19th century America.
Joseph Smith himself, two years after the Book of Mormon was published, wrote that he "was mearly instructid in reading and writing and the ground rules of Arithmatic"
Here's what Joseph wrote in 1832 (original spelling retained):
I was born in the town of Charon [Sharon] in the of vermont North America on the twenty third day of December AD 1805 of goodly Parents who spared no pains to instructing me in christian religion at the age of about ten years my Father Joseph Smith Siegnior moved to Palmyra Ontario County in the State of New York and being in indigent circumstances were obliged to labour hard for the support of a large Family having nine chilldren and as it required the exertions of all that were able to render any assistance for the support of the Family therefore we were deprived of the bennifit of an education suffice it to say I was mearly instructid in reading
andwriting and the ground of Arithmatic which constuted my whole literary acquirements. 
Joseph's wife Emma stated the Joseph "could neither write nor dictate a coherent and well-worded letter, let alone dictate a book like the Book of Mormon"
Who would have known Joseph's abilities and weaknesses better than his wife?
Joseph Smith could neither write nor dictate a coherent and well-worded letter, let alone dictate a book like the Book of Mormon. And, though I was an active participant in the scenes that transpired, and was present during the translation of the plates, and had cognizance of things as they transpired, it is marvelous to me, 'a marvel and a wonder,' as much so as to anyone else.
- "Could Joseph Smith have written the Book of Mormon?", MormonThink.com http://mormonthink.com/josephweb.htm#full
- Joseph Smith Letterbook 1, pp. 1-6. Published in: Dean Jessee, Personal Writings of Joseph Smith. This text was copied from Wikisource. The editor notes that insertions are indicated like this and deletions are indicated like this. Text in blue is in Smith's own handwriting, the remainder in the handwriting of Frederick G. Williams. off-site
- Joseph Smith III, "Last Testimony of Sister Emma," Saints' Herald 26 (October 1, 1879): 289–90; and Joseph Smith III, "Last Testimony of Sister Emma," Saints' Advocate 2 (October 1879): 50–52.