Teacher Promises If Whole Class Get's An A On Test, He'll Wear A Scooby Doo Costume And Bring A Kid's Champagne. Class Did Their Best, He Came As Promised.National Teacher Appreciation Day, also known as National Teacher Day, is observed on the Tuesday of the first full week in May. In 2017, National Teacher Day will take place on May 9th. This day is part of Teacher Appreciation Week, which is the first full week in May of each year.Teachers deserve thanks and praise every day of the year, but this is a special opportunity to recognize the incredible impact that a great teacher can have on your life, inside and outside the classroom.