Use math drawings to represent subtraction with up to two decompositions and relate drawings to a written method

In this lesson, students continue to deepen their understanding of subtraction as they move from the concrete stage to pictorial representations. They will model decompositions using the chip model while simultaneously recording the changes in the written form. Students draw a magnifying glass around the minuend, then ask the question, "Do I have enough ones?" They refer to the chip model to answer and exchange a ten disk for 10 ones when necessary. They continue to record changes.