The graduation rate for schools with after-school programs is sixty-five percent higher.
Explanation:
It shows that it keeps students in school till they graduate and its due to the fact that the schools had after-school programs. It shows the fact that they are not leaving because they have something that they enjoy doing after school but can only do them if they stay in school.
A colon is used to demonstrate a list. In this case, you are listing the places where funding for libraries is not prioritized. Thus, it would be appropriate to insert a colon before it.
