How has the introduction of the Common Core Standards in recent years affected teaching in the United States?

With the advent of Common Core, teachers realized that they could no longer teach as they had for the last 30 years. Instead, many who had been "in the business" for a long time discovered that they would need to allow students to have more hands-on experience in order to prepare themselves for college and career.

Why did Maslowe place food, shelter, and clothing at the bottom of his hierarchy of human needs?

For Maslowe, it was simple. Food, shelter, and clothing are the very basic necessities that one needs in order to survive. Without these things, humans are unable to attain the higher needs of love and belonging, and ultimately, self-actualization. One level builds upon another in his hierarchy.

When it is it appropriate to use the Oxford comma?

I am a big proponent of the Oxford comma, and here's why: Although it can be entirely appropriate NOT to utilize it, placing it after the next-to-the-last item in a list or series virtually guarantees that you will not be misunderstood. So... when in doubt, do!