Lack of Emphasis on Prescriptive Grammar
Students don't learn grammar in schools the way they used to, according to glencoe.com.
Five decades ago, English teachers taught the subject as a set of rules to be memorized. Sentence diagramming and drill exercises were the norm in this "prescriptive" education.
Today, schools emphasize "descriptive," or transformational, grammar, which is a user-oriented teaching style, as glencoe.com notes. Students' self-expression and actual speaking styles are emphasized over correct, proper English usage.
A piece in the New York Daily News describes a few of the grammatical errors that have become acceptable in daily speech due to the changing educational philosophy of the last 40 years. For example, split infinitives have become common. Moreover, adults often speak ambiguously without realizing their sentence errors. As the Daily News notes, one might easily instruct someone, "tell X to be here on Wednesday," without adequately conveying, as they intended, when X needs to be "here." The sentence, as structured, merely expresses that X needs to be spoken to on Wednesday.
Regardless of trends in classroom writing instruction, businesses and higher education institutions will still expect young adults to be able to utilize correct English. Spelling and grammar checks will become all the more imperative for professionals who wish to communicate effectively.