Here's page 3.
Now, an air flight! Ride on Time.
I'm pretty sure the katakana says "raido", for "ride", rather than "raito" for "right". I'd expect a phrase like "right on time", but I'm going with "ride on time" in the expectation that this is a pun.
This is really fun! Io, isn't this your first time on a plane?
Kurin refers to him as "Io-kun" as a form of familiarity, still as just a friend. I'm dropping the "-kun" here because it's kind of distracting.
Ah --, I guess...
She's really light-hearted. I wish I wasn't here as just her babysitter.
"kiraku" is "at ease" or "comfortable" Neither phrase works well for Io, so I went with "light-hearted". Maybe I should have gone with "carefree". Io then thinks that he wants to be here not in the role of babysitter. So, I chose "not just as her babysitter" to show that he wants to be here, but as a friend, not a caretaker.
This is terrible! While I wasn't paying attention...
Kurin's papa, Sensei Higashimori.
Kurin won a free trip to Okinawa from a Shonen Champion prize drawing.
Champion doesn't offer such a great prize. But, that's good, right?
"doesn't offer such a great prize" doesn't come across quite right, but it's in keeping with the original text. It may have been better to say "Champion doesn't offer such high-ticket prizes".
In this case, "lucky" is used to mean "that is lucky", or "that's a good thing".