I will like to throw more light on this your definition of Bitcoin because It lacks the crucial ingredients through which Bitcoin stand for.. Because I would have think instead of defining "Bitcoin as a digital currency launched in 2009 used as a peer 2 peer to facilitate instant payment".. it would have been better you had defined it this way "Bitcoin is a decentralized digital currency launched in the year 2009 by Satoshi Nakamoto, that is independent on its own, not control by either the central bank or government, and can be used to transfer money from one person to another in seconds"..
That might be his way of defining. Whenever we talk about bitcoin, the ultimate thing that gets into discussion will be the money making. Maybe to make his neighbours get interested towards bitcoin, he might've started to define it in such a way followed by the payment features. Through this thread he'll get more suggestions which could help him improve the teaching method.