Criminal record checks aren’t a big deal, provided you do not have a record, but anything online is an issue. This isn’t just for your background check, but also for future positions. You MUST remove all traces of your online self. Untag and remove any inappropriate pictures on Facebook (ask your friends to remove pictures they posted), untag all of your other photos that seem professional looking. Update all of your privacy settings so you cannot be searched (even change your online names from your real name). There are ways beyond privacy settings to get into people’s social media accounts.
A friend of mine was at a job interview for a teaching position, and they pulled out a photo of her intoxicated from Facebook, asking her if this was the professionalism in her everyday life she mentioned in her interview answers. She clearly did not get the job.
Additionally, your future students (and even parents) will try SO HARD to find you online. Do you really want them to find you?
Look up some info online for social media professionalism and etiquette.
Teaching In Real Life 