The first time Ye Zhigang stepped into Xiao Min's room, he could not believe a teenager could slip out of control to such an extent.

The 15-year-old Internet addict had dropped out of school, and his mother had hired a private teacher - an old man who was kneeling at the bedside begging Xiao Min to focus on a math formula.

The irritated boy lying in bed slapped the teacher's face, broke his glasses and yelled: "Get out of here. Let my mom buy you a new pair of crystal glasses!"