[kisito]

13 is usually the start of those trouble teenage years. They are starting to feel too cool for school and would only participate in certain activities. Also they have so much energy for fun not studies. The book is quite boring. So the teacher is forced to reinvent activities.
I usually ask them what they want to talk about. Based on their topics of interests, I plan my lessons activities around those.My teenage boys are usually into topics like: movies, computer games, sports etc.
Games that work for me are:

Running dictation - It is a good alternative to a boring reading comprehension. This page has a guide on how to play. It can also be communicative.

Chinese Whispers also works for me. This is how to play

Hotseat with flashcards always gets them talking. This is how to play.

Mallet Mallet is a good one too. Mallet mallet is good for word review. This is how to play.

There are more but first try these ones. The beauty behind these games is that there is little planning involved.

For other activities I recommend building lessons around videos and music. A popular English or movie that can trigger imagination will help. I use Mr. Bean a lot because Mr. Bean has a lot of short episodes that are related to the most topics we teach. A good example of Mr. Bean lesson plans are here

These activities work for me. Hope they can be of help.