Remember that generalizations often need qualification. Avoid value-laden words. Use verbs of action as much as possible. These show the subject doing something, not just being something. They also more clearly show who is doing what to whom.
Teachers reward girls for being . . . .
Use concrete nouns instead of abstract words. A concrete word names something you can see, touch, taste, smell, or hear. Abstract words sum up the total effect of many particular, concrete things. Speak directly to the subject, rather than with circumlocution. I thought you might be interested in someone else's ideas about man's evolution regardless.