Assessing knowledge

Are there reasons to be skeptical of your knowledge claims?

There are many reasons to be skeptical of what we know.  Because much of what we have learned in school, for example, we have not seen ourselves, it is hard to confirm what we know. Some choose to be skeptical about all global matters, while others simply question academics.
One reason to be skeptical is because of the question, 'how can we really know if knowledge exists?' Although the world needs standards to communicate, sometimes they are also questionable and it is hard to find a common ground to base future claims on.
Because the world's population is so large, there are little opportunities and people have little time to attempt to confirm what they know.  Not only is it imposible, but also inconvenient and ineffeciant.  Therefore, we have every right to be skeptical of knowledge.  Information and knowledge in the 21st century is readily available, unlike the past, making it even more likely for people to be skeptical, but not act on it.
One way to circumvent the confirmation problem would be to simply see or experience something for yourself.  However, this is not very convenient or efficient, and would be a great amount of trouble for one to go through just to confirm something trivial.  Therefore, it is important that people have a trusted number or sources; ones that they know are right from what they have seen.  This would greatly minimize the skepticism and provide for a clearer view of the world.