The original module, created by Eureka Math, consisted of 19 lessons. It has been altered to include the first 10 lessons involving place value of multi-digit whole numbers, comparing multi-digit whole numbers, and rounding multi-digit whole numbers.  Students work with large numbers using familiar units (hundreds and thousands) and develop their understanding of millions by building their knowledge of the pattern of times ten in the base ten system on the place value chart. They learn to recognize that each sequence of three digits is read as hundreds, tens, and ones followed by the naming of the corresponding base thousand unit (thousand, and million).