Some people struggle with reading black text on a white background. Irlen Syndrome is a visual processing disorder where the brain struggles to handle certain wavelengths of light. Symptoms might include poor reading comprehension; problems tracking lines of written words, which may seem to wiggle or move around the page; problems with neat handwriting; frequent headaches; and/or issues with depth perception, like struggling to catch a ball. See http://irlen.com/index.php?s=what for more information.
While you’re clicking around, take a look at how a reading selection may appear to someone with Irlen Syndrome: http://irlen.com/distortioneffects.php
Treatment consists of using a tinted, color overlay (the color depends on the particular light wavelength that is problematic) when reading or by having specially tinted lenses put into glasses by an Irlen specialist.
How can social media help? Flickering computer screens could make distortions worse, but colored backgrounds for a web page or tinted screens that go in front of the monitor could help. Podcasts and other aural media to accompany or even to replace a reading may take some of the pressure off a student straining to keep words in focus.
Some doctors and scientists doubt that Irlen Syndome even exists, and they argue that people who are diagnosed with the disorder may have underlying vision problems that need corrective lenses or other therapies: http://www.reuters.com/article/2011/09/21/us-colored-overlays-idUSTRE78K4J420110921
As for me, if a yellow-tinted piece of plastic can help a student feel more confident about reading, I’m all for the placebo effect!