That's right, I said it (que the what's and how dare you's for later). The article "Twtr? It's majorly bad" written by Laura Clark was a pile of baloney, with no end to providing fake and misleading information. Mrs. Clark, are you related to Donald Trump by any chance? Your facts are all wrong.
Point numero uno, Text Speak (as you like to call it) was incarnated by the fact that our bully cellular companies charged our texts on how many characters we used in the text. Thus, abbreviations such as u, gtg and brb were invented. Mrs. Clark I don't know about you, but from what I see in this world, we are always in a rush and live in a very fast moving society. However, due to texting we can communicate easily with others at any given time. Do you think that the society in which 40% of people get lesser than 5 hours of sleep has the time to write perfectly worded "standard" English in their texts? The whole point of texting, Mrs. Clark was actually to save time, not to "brutally murder" it as you have suggested.
This transitions onto my next point, which challenges the validity of your observations in students. You say that your students use slang such as "innit", "phat" and "majorly bad" in their work. Really? To counter this, I would first ask you to go check their EXAM papers (something which kids actually care about) and then give a few detentions to the cheeky few lads and lasses which have pulled the teacher's leg by including the slang in their work. Evidence, to suggest that your claim isn't true is provided by Mr.David Crystal, a linguist at London College. He visited several schools, asking students whether they use the slang lingo in their work; the poor man received weird stares given to those of a madman and rounds of laughter for asking such a stupid question. If that isn't enough for you and you are so scared that modern day abbreviations "wreck" English, look at the research conducted by Stanford, which shows that students in 2006 had papers six times as long as those of students in 1916. Why? Because of the constant exposure modern day students have to texting, which creates a greater comfort with the language they are learning.
I've got to say Laura that was some majorly bad research you did. (LOL)
My final point is the useful nature of texting and how you should apply some simple logic. A good friend of mine, Mr. John McWorter (Recently on TED) actually said something which you should hear ; "Texting is a very useful tool for new English students, because of the fact they are constantly looking at English texts, reading them and then sending them out again". You heard right, Texting means invaluable constant exposure to the Language. Add this to the fact they are reading, writing and enjoying all at the same time, ensures its a win-win situation.
In conclusion Mrs Clark, I think you shud jus chillax, and let things flow. In all reality, like my friend John puts it; texting is just "Fingered Speech", its just a way for people to write the way they speak. Texting is an organic item, which hate it or love it, is here to stay. With the invention of Facebook, Twitter, Whatsapp and etc. best of luck trying to keep your students away from their phones. However, not to fear because texting isn't half as dangerous as you claim!
GTG, Ttyl?
