# K.2 - Compare and Order Sets

The student, given no more than three sets, each set containing 10 or fewer concrete objects, will

a)  compare and describe one set as having more, fewer, or the same number of objects as the other set(s); and

b)  compare and order sets from least to greatest and greatest to least.

### BIG IDEAS

• So that I can understand more and fewer
• So that I can understand  that a group of objects is a set
• So that I can understand that a group of 5 marbles is the same size set as a group of  5 basketballs

### UNDERSTANDING THE STANDARD

• A set is a collection of objects.
• Sets can be compared by matching, lining up the objects, visually estimating magnitude, recognizing quantities without counting (subitizing), or counting the number of objects in each set.
• Comparing sets is an extension of conservation of number (e.g., 5 is 5 whether it is 5 marbles or 5 basketballs even though 5 basketballs take up more space). When comparing objects, the set can be arranged differently while still containing the same number (e.g., 5 marbles in a cup is the same as 5 marbles on the floor).
• Comparing objects is an extension of cardinality.  Cardinality is knowing how many are in a set by recognizing that the last counting word tells the total number in a set.
• Students are generally familiar with the concept of more, but may have had little experience with the term fewer.  It is important to use the terms together to build an understanding of their relationship.  For example, when asking which group has more, follow with which group has fewer.

### ESSENTIALS

 The student will use problem solving, mathematical communication, mathematical reasoning, connections, and representations to Compare and describe no more than three sets of 10 or fewer objects, using the terms more, fewer, and the same. (a)Given a set of objects, construct a second set which has more, fewer, or the same number of objects. (a)Compare and order three or fewer sets, each set containing 10 or fewer concrete objects, from least to greatest and greatest to least. (b)

### KEY VOCABULARY

Updated: Aug 22, 2018