Music Theatre International (MTI), the group that licenses theatre organizations to perform musicals like West Side Story, strictly forbids changes of any kind to the original book, music or story. The company's website page for West Side Story specifically notes, under the "Show Billing" tab, that the cast and crew are not allowed to add the male Sharks to "America" or switch the places of the songs "Cool" or "Gee, Officer Krupke". The company notes that the license is not giving permission to perform the movie version in any way. The performance that the school in the show presents would be considered a violation of contract in real life.
The fake IDs were from Hawaii. An obvious nod to the movie Superbad (2007).