Excerpt from this article:
If you ask a group of kids if they ever felt left out when they see images or videos posted in apps like Instagram, Vine or Snapchat, they will have a lot to say. Each of these apps can include images and videos of groups of other friends that may not include the viewer.
When I posed this question to this group, the middle schoolers all said that this happens all the time—and can be hard to deal with. They all agreed that it is better not to lie or make excuses if you are busy with one group of friends and another friend wants to hang out. Better to say, “I have plans” than to lie and say, “I have too much homework,” and then share images of yourself at spending time with other friends.
I asked them if they think kids post images with the intention of making others feel excluded. Most of the kids were reluctant to admit it—they’ve been on both sides of this issue. One boy suggested that other kids post pictures in the moment without really thinking about it.
…They were able to admit that if they had other friends over, it might be tempting to take and share pictures. When I asked why she would share pictures at all, one girl said that she wants to “show that she has a life outside of school.” Another kid said, “it is fun to share when you are doing fun things.” Other kids pointed out that social media is a way to mark the moment and preserve memories.