Faking attention means attention which is not real,which means that u r not really paying attention towards something just appearing as if u are paying real attention.
Example:You r thinking about something which is going to happen quite after sometime like u have been selected for volleyball and u have the matches after lunch so u start thinking about in the 3rd period itself and do not pay attention to the classes and nod ur head as the teachers are explaining this attention is called fake attention which will disturb ur listening.