on academy vs in academy

Some examples from the web:

• Lincoln wasn't on academy grounds.
• You're telling me there's no way that gun could possibly be on academy grounds?
• In response, police have ordered all weapons on academy grounds to be confiiscated.
• Apparently, his squadron was practising on the Academy flight range near Saturn.
• It was in my last year on the academy.
• You didn't want to bring the sauna on the academy.
• There's been an attack on Corbulo Academy, excessive casualties.
• His original badge will always hang on the academy wall, but... made this one for you.
• And he should be done with that in two weeks, and then on the Academy stage.
• Is there anything on your academy application that was true?
• This comprehensive comparative information on football academies in Member States and on home-grown players is not available at present.
• In 2006, the Commission launched a study on sport academies in Member States, including the issue of home-grown players.
• I've also checked with the military academy on Kora ll.
• He was rejected from the police academy on four separate occasions.
• And, you know, it's been my dream to be on the Academy Awards, and finally I am.
• Truth is... every soul who knocks on those Academy doors asking to serve, they're already heroes because they were born that way.
• He's on vacation from the Academy.
• And an Academy Award on my shelf.
• One example he cites centers on the prestigious national academy of sciences.
• She did her dissertation on Carroll at the academy.

Some examples from the web:

• It's well covered in Academy training.
• He's in a military academy in Fort Lauderdale.
• We met back in the fire academy in 1987.
• There was a big fire at a college prep school Gas explosion in Yonghwa academy in Dae-jeon around 1am this morning.
• You recited poetry in the academy at springtime.
• I flew something similar back in my Academy days.
• See, I've spent my whole life in military academies.
• Brigades is the biggest event in this academy all year.
• They taught us how to deal with delinquents like you in the Academy.
• So you're fresh meat hatched in the academy.
• I was remediated in the academy also.
• Heard you helped Internal Affairs uncover a mole in the academy.
• Okay, he's not enrolling in the academy.
• All they ever taught us in the Academy was how to do paperwork.
• Look, half the students in our academy are here because they are troubled.
• I'm sure you're not the first midshipman to engage in an academy prank.
• That's what they teach in the academy: Catch them off guard with irrelevant questions.
• In the academy, I heard about you.
• I mean, it's not a total lie. I was in the academy.
• Then he winds up in gladiator academies like Chino and Tracy.