If you are anywhere near Santa Rosa (CA) this summer, check out the Charles Schultz Museum and its exhibit on Title IX. I found out, while researching the Women's Equity Action League's involvement in the passage and enforcement of Title IX in the 1970s, that Schultz was a supporter of women's equality and, more specifically, of women's sports and Title IX. I found copies of some of Schultz's cartoons in the WEAL archives. It's not surprising. Even the cartoons that were not more overt statements on women's equality, showed the girls of the Peanuts gang playing sports--and playing them well.
Here is a strip that remains relevant today that addresses the possibility of injury for girl in sports (kind of).