Please don't induce labor for convenience! My reasons for saying this are:
A "due date" is only accurate within two weeks either way (a birth 2 weeks before or 2 weeks after 9/8 in your case would be considered normal), so by going a week before 9/8 you run the risk of bringing that baby into the world up to 3 weeks early, and
the incidence of "preemie" related physical problems in babies has escalated because of an increase in induced labors and elective C-sections combined with wrong date "guesses" by doctors.
Every mother that I've heard from who has been induced has had a long, painful, difficult, or complicated delivery (including some unplanned C-sections.)
Birth is a natural process, if we let it be! Babies know when they are ready to be born, they've been doing this by themselves for all of human history.
The school start "issue" is overblown and your child will do fine whether they start school at 5 or 6, younger kids in the class catch up quickly, use your own judgement based on the individual child. And there are great pre-schools if s/he misses the cut-off.
Please just relax and enjoy the birth and arrival of your second child and everything else will work out.