Using the correct search terms will help you have more success in finding the kind of picture you need. Boolean searches allow you to combine words and phrases using the words AND, OR, NOT (known as Boolean operators) to limit, broaden, or define your search.
Here is a list of helpful terms for your picture search.
inequality
equality
sports and equality
education and equality
African Americans
civil rights and children
womens rights
immigrants
multi-racial group
race and children
freedom and children