Here is a fun worksheet that will challenge your youngsters. They alphabetize all of the words in the left column, and then they do the same for the words in the right column. When they are finished they'll see that they've properly ordered each list because the words in the left list will be opposites of the words on the right.  

Common Core

RI.K.3 RI.1.3 RF.K.3.a RF.1.3.a L.K.5.a L.1.5.a