For a fun game to practise speaking you could give some pupils questions and others the answers, or funny multiple choice answers. Tell the group that the multiple choice answers must match up and find their question.
To keep the class on task have various incentives such as giving a time limit, which is quite tight, so not everyone will finish. When you use this method regularly the students know they do not have time to mess around. You can also give a reward or point to the first group or groups to finish.
You can also say things like, “remember conversations need to be about finding your question or answers”.
See the website below for more ideas speaking games for children.
Receive free games and ideas to make teaching children more fun on: http://www.teachingenglishgames.com