Create Ad-hoc wifi on Android (Samsung galaxy note 3)

I am creating a website using flask (python) to hold pre-downloaded episodes of anime and cartoons to take into school and host between me and my cartoon club. I want to run it on my Samsung galaxy note 3. Python is not a problem but I need to create a private, ad-hoc (I don't want all my data used up) network to run the site on and let my friends connect (also android phones, mostly). My phone is rooted, but theirs aren't. I can run a private hotspot but I don't need the whole internet, (nor the exorbitant costs). Any ways to do this?