If you're studying Chinese and aren't already reading graded readers, pick one up IMMEDIATELY and start reading TODAY. It's generally quite difficult to find suitable reading material for learners in Mandarin. Volumes like these (and there are many others as well) make reading Chinese so much more effective and enjoyable for learners. This particular volume is targeted towards low-intermediate learners, I believe, but it would be useful even for advanced learners. This is the first graded reader I've ever read, so I can't compare it to others, but it seemed like this one was of excellent quality. The story was quite engaging...and this is coming from someone who doesn't normally read a lot of fiction. Eventually, I practically forgot I was reading Chinese, and simply felt like I was reading a great story.
If you've read other graded readers that you like, please let me know!