Here are a few resources to help you understand why it is important to limit screen time.
Screen Time Is Making Kids Moody, Crazy and Lazy https://www.psychologytoday.com/us/blog/mental-wealth/201508/screentime-is-making-kids-moody-crazy-and-lazy
Ten Reasons Middle Schoolers Don’t Need Social Media http://community.today.com/parentingteam/post/ten-reasons-middle-schoolers-dont-need-social-media
4 Things to Know about “Screen Time” https://www.integrativecounselingandneurofeedbacksolutions.com/single-post/2016/02/10/5-Things-to-know-about-screen-time
You can check out the American Academy of Pediatrics recommendation on screen time here: https://www.aap.org/en-us/about-the-aap/aap-press-room/Pages/American-Academy-of-Pediatrics-Announces-New-Recommendations-for-Childrens-Media-Use.aspx
Find out more information on screen time and other educational topics go to this educational resources Facebook group: https://www.facebook.com/groups/playeducationalresources/