Macmillan graded readers
It could also help to know the age.
ps. More importantly, what's your objective? Graded readers are usually fine for the-so-called 'reading for pleasure' with little visible outcome. To get the most of reading in class, you may want to explore today's newspaper and magazine articles that could bring in a lot of good language and a bit of fresh air. It may vary from country to country but generally speaking UI learners can cope with the newspaper language. Regarding reinforcing reading sub-skills, there are a lot of 'Reading Skills' editions like Q-series: http://elt.oup.com/catalogue/items/g...ge=en&mode=hub or a great deal of FCE reading paper tests/activities available on-line in gbytes. Last but not least, consider using reading games - they are real fun.