The term GRADE SCH. SUBJECT is composed of three words: Grade, School, and Subject. Grade refers to the level of education a student is in, such as elementary, middle, or high school. School is the institution where students attend classes and receive instruction. Subject is the topic or area of study that is being taught. The crossword solutions for this term are ARITH (5 letters) and SCI (3 letters). Arith is short for arithmetic, which is a branch of mathematics that deals with numbers and calculations. Sci is short for science, which is a field of study that involves the observation and understanding of natural phenomena.