Years back I faced the challenge of gently waking up a pre-teen boy for school, a feat his mother said was just not possible. Took me only a few days of trial-and-error to discover what worked on him; simply ask him a question. Something like "Anything special going on at school today?" or "When's your next math test?". As soon as his brain got engaged thinking of the answer, his body followed along and he got up, dressed and came down for breakfast before heading to school. That simple.