In the United States, Denmark and Sweden, an apple (polished) is a traditional gift for a teacher. This stemmed from the fact that teachers during the 16th to 18th centuries were poorly paid, so parents would compensate the teacher by providing food. As apples were a very common crop, teachers would often be given baskets of apples by students.
Giving an apple to a teacher is also the origin for the term "apple-polisher," which was first recorded in the late 1920s. Apple-polishers also referred to as bootlickers or toadies,teachers pets .