I lost my Iphone at school and it has no service at all can i still find it?

OK so as the title says I lost my Iphone at school and it has no service at all and So far I asked my teachers and went up to the front office to see if anyone gave it up but yet no sign yet. I lost it yesterday around 6 per. That was the last time I had it and when I went it 7th per. During that time I was checking my pockets for my phone and I could t find it I was freaking out and checked everywhere for my backpack. Now i'm trying to locate my phone using the Find My Iphone app on the iCloud. I put it on Lost mode and I put a little message saying call me back for my phone but it says my phone is offline and they only way my message is gonna get to my phone is by connecting to Internet but I have a lock on my phone and They can't get in my phone and turn on the Wi-Fi to see my message. So are there any chances I can find my phone back That is my very first phone I ever had and I really am sad. Any replies can be useful and helpful thanks.

Use find my IPhone to lock the phone. If it turns up and someone turns it on, it will show its location.
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