What kind of learning material we use in class and whether we use any at all is entirely up to you. However, unless you have other requirements I suggest that we focus both on more formal and less formal/idiomatic language use.

For more formal language practice I prepare articles from well known online newspapers:

sample article

To practice less formal/idiomatic speech and to improve your listening skills I can recommend the following AUDIO+TEXT ESL lessons

text	audio  (easier) 15MB	audio (harder) 10MB

Watching native speakers speak natural English is essential in getting better! That's why I prepare short video clips which  we can watch in class. I vary the rate of playback
to make it slow enough for everyone to understand.  Here is a sample dialog between a popular American  talk show host and a world class British chef :-)

If that should not be enough, or you might need to work on something easier, or would also like to do something different, then besides other newspaper articles, internet and radio material, news reports, etc. we can also work on other kinds of assignments, such as: