What you can also do is split the class into several smaller groups or activity centres (if you can organize desks that way, or use a carpet/blanket for a floor activity for some) and then play various word games with them at the same time. There are all sorts of word games available from this site, but to keep my explanation simple:
group 1 - MEMORY: they can play a simple memory card game in which you can use word cards with simple sentences or phrases, or even pics to match with words as memory pairs
group 2 - MATCHING: they can get two lists of e. g. questions and answers for meeting someone to match (e. g. What �s your name? + I �m John., How old are you?+I �m14., etc.)
group 3 - SORTING OUT: give them 3-4 envelopes with categories written on top (e. g. animals, colours, numbers, food) and then give them lots of word cards(cat, sandwich, dog, yellow, three...) all mixed in a pile and they have to sort out the words into proper categories/envelopes
group 4 - YES/NO: - give them a list of statements about sth you covered, some statements are true, some false, and they have to read them and add the words yes/no to agree or disagree with your statements
group 5 - FILL-INS: - give them a huge poster with a simple text about sth you covered and have them fill in the missing words
group 6 - CORRECTING: - provide words (or a simple text) which is full of spelling mistakes and they have to correct them
Each game is first explained to all the sts, and then they have a certain amount of time to do the activity (5-7 mins, you decide). Then you take their results (you can use different colour paper for each group) and then they switch centres. The goal is to cover as many centres as possible. You have to prepare the activities well and control the whole thing, but it �s fun and very effective, especially if you give them points for it and give the best team a prize (a simple chocolate will do). This is a great way to revise material for a test, because afterwards you can provide all the game tasks for them as a worksheet or even the test itself and have each st do every task for homework or as a test.
Btw, they should have a statue in your honour at your school for working with such a huge group at once!!! It �s sooooooooooo difficult, and still you have the motivation to ask for advice here! Congrats on your effort and I really hope it works out well! Hope you �re saving your voice, having lots of mild tea for your vocal cords, and I hope your teenagers appreciate your work!
Anita