Not all friends in your team would be ready to play such online games, but you could still use their names in the team. You could play the game in their name but by creating the account with the email Id created with their name. Since you could create the user name as per your wish there is nothing that you are doing harm to your friend who is not into online gaming world. However, since the process of creating the account and bringing it to a certain level would be a lengthy process, you could buy lol accounts from ULA and then give the details to your friends.
It is possible some of your school friends have taken a different course of study and hence are busy with exams and you have completed the exams much early. While you could enjoy playing the game from scratch and successfully cross each level, you could buy the accounts for your friends and have them enjoy the game from the same level as you are playing. You could get their inputs on how you all could play together and what time you all could login at once so as to play the game without having to face the defeat.
Most of the times, it is noticed that the phone with low battery is a major cause apart from the gaming strategy that is employed. Hence, it is important that all your friends take an oath that you would not overuse your phone just before starting the game and thus cause trouble to other friends and team members that are actively playing the game with lot of commitment and enthusiasm. Buying the accounts would be easy and since the payment options would be secure you could plan to buy them even on your credit cards or any other wallets that the seller would support.