Students must know the divisibility rules. This knowledge is crucial with fraction skills. These rules need to be memorized and practiced often. They will be used year after year throughout the remainder of their schooling (and beyond). Here are some links to help you learn or brush up on your divisibility rules. Students need to know the basic rules; 2, 3, 4, 5, 6, 9, and 10. There is also some practice with other rules.
Divisibility rules practice game
Divisibility Rules Concentration
Teacher Tube Video/Song
Fifth Graders singing "We Will Divide You!"
A Song for the 3's and 9's Rules