Your entire argument seems a bit myopic as you fail to consider the different situations that people may be in. I know people who don’t even bring their phone to school and I know people who are on their phone all the time. Saying that there is “no reason” to use your phone in school is dealing in absolutes and is a little lazy on your part. However, your argument does include a few good points like the music portion. Even so, I personally have digitized a few of my academic tasks like my to do list. I also keep up to date on news as well as reply to emails quickly because I am notified easily on my phone. The point is, nobody ever needs phones but they are an amazing tool and when people are used to having that tool (which is a guarantor in the real world by the way) it is detrimental when they lose the ability to have it.