Import Bulk Users via CSV without notifying them

Hi... I want to see if there's a plugin or trick to importing (about 500) users without notifying them by email. This is a school and I can't rely on the parents replying to email and I'm trying to avoid manually adding them one by one. I see the "ADD NEW USERS" plugin but it looks like it sends a notification/signup email and gets them to sign in. Is there another way of doing this without this notification? Thanks!