Here's some remedies...

http://www.raisinglifelonglearners.com/gifted-children-need-less-sleep/

My DD10 did not take nap since she was 3 (unless we were driving) and we had to work with her pre-school so that she gets exemption not to take nap. Now, she bargained with us that if she is taking HS level classes, she should be able to stay as late as HSer. Well, she does not have HS level home work but we compromised.