First, students are in a stupor following the winter holidays. You can't continue where you left off, and there isn't enough time in the semester to start something new.
However, you have to motivate students and have them working with you to get over the final push in the face of oncoming tests/exams and FREEDOM!!
What to teach? Buzzwords are the perfect first class back topic.
Step One - Their buzzwords.
Get students in groups and introduce the term 'buzzwords'. In Japan, the Yukan company makes a list of most popular buzzwords, so I write them on the board and have students explain what they mean in English. Have each group take one word, research it for 5-10 minutes, then explain its origin, use, and meaning.
Step Two - English buzzwords
Although the English world doesn't have one authoritative ranking on English buzzwords, choose one that seems reasonable to you and repeat the above procedure, having each student group explain one buzzwords. Tell students that if they cannot find the word in the allotted time that is OK, as researching pop culture there is no penatly, but they must at least make a good effort.
Be non-judgmental in your comments and praise students for their effort.
I have included 2016 English and Japanese buzzwords below:
English Buzzwords 2016
1. webrooming 6th December 2016
2. liquid biopsy 2nd November 2016
3. nowcast 4th October 2016
4. mic drop 13th September 2016
5. sharewashing 2nd August 2016
6. moto-doping 6th July 2016
7. swipe 8th June 2016
8. Brexit 3rd May 2016
9. crowdbirthing 7th April 2016
10. rainbow 26th February 2016
11. vapourware 23rd February 2016
12. Physical Cookie 9th February 2016
13. sandscape 2nd February 2016
14. stuffocation 19th January 2016
Japanese Buzzwords 2016
Yukan 33rd ranking