From the article, another study that "The finding sounds 2G2BT, but British researchers say text messaging doesn’t harm literacy. In fact, those who regularly text have better reading skills, despite their frequent use of phonetic spellings, abbreviations, and omission of vowels." (link). LOL.
I do think this was a creative way for the teacher to get his students involved. It takes an excellent teacher to engage his/her students, and that's key in teaching.
I also could understand the study results about texting. After all, those who text still must gather their thoughts and write about them. And, all texting does not use abbreviations.