On the Google.com home page in the United States you will see an animated Google logo, Doodle, with a large pencil and five smaller pencils walking and learning. The Doodle is to represent Teacher's Day in the US, today is National Teacher Appreciation Day.
In many countries, Teachers' Day is a special day for the appreciation of teachers, and may include celebrations to honor them for their special contributions in a particular field area, or the community in general.
The Google Doodle does says Nate Swinehart (@unlevelednate) designed it and he described the doodle as:
It’s impossible to measure the impact of a great teacher. The curiosity they ignite will become the mathematical theorems, medical breakthroughs, and beautiful art that make the world a better place. Today’s homepage by artist Nate Swinehart honors the invaluable civil servants all across the United States who’ve dedicated their lives to molding a thoughtful, compassionate generation of citizens. And to making sure everyone does their homework.
Forum discussion at Google+.