Re the lying - you should know it's not that unusual. I can't remember her name - but there was a researcher who did the first compilation of characteristics of profoundly gifted kids - more than 60 years ago. I remember reading the characteristics and blushing when I realized this applied to gifted-but-not-PG me (as a child - I think I'm better now): a tendency toward extreme mendacity. Maybe somebody who remembers her name can link to the actual article ....
So anyway - teaching them that lying is not the right way to go is soooooo important. And aeh's words are wise here. But I just wanted you to know you're not dealing with some weird character flaw. I sort of freaked out when DS7 went through this phase.
