1. While I can most certainly understand the reservations that some people might have regarding the use of women's sexuality in sports to further the "male gaze," these options should not be stripped from women solely because it may make others nervous. Furthermore, given the right context and the right material, these opportunities might be a way for female athletes to express a healthy form of sexuality and gain ownership over their bodies. In the case of the Canadian women's biathlon team who released the nude calendar, it does not seem as though the team itself were forced into it - they actively participated in the event in order to raise money for their own Olympic run. They are hardly nude, and the photography and images are rather tasteful. In my mind, this would only be objectionable if the women were somehow forced into it, or if the process of creating the calendar were anything but amicable and consensual, and the women were made uncomfortable in any way.
There may be some ugly things to say about our society that these women have the best chance of raising money for their Olympic expenses by posing nude; the sheer amount of money that goes into things simply because they have beautiful, scantily clad women on them shows a tremendous shift in priorities that must be addressed. This is usually done through the feminist theory of the "male gaze," wherein women are objectified as sexually desired beings disproportionately to men (https://wiki.brown.edu/confluence/display/MarkTribe/Visual+Pleasure+and+Narrative+Cinema). However, discussing the objectification of women should not trump the woman's own desire for agency and sexual expression - if the calendar was their idea, and they are comfortable with it, it should not matter.
2. (i) I honestly do not think Billie Jean King's attitude towards her persona as an athlete would not have changed if she were heterosexual. Certainly, her comment about hiding your true feelings is particularly cutting when you think about her hiding her sexuality, but even if she were straight this would be the case. Public scrutiny is relentless regardless of sexual orientation, particularly for women in sport; the slightest sign of weakness or timidity means you are not qualified to play "a man's game." She would still be hiding things - thoughts about herself, about the game, etc. - if she were straight, so her strategy would have remained the same.
(ii) The issue of sexual orientation is a tricky one, especially in the sports world. The business of sports is geared so much toward masculinity and heteronormativity that it is nearly impossible to continue as either a heterosexual female or a homosexual player of either sex. Societal pressure could be lightened if society placed a much lighter emphasis on the players' personal lives than they did their performance during the game. This way, players could be free to be whoever they were without fear of recrimination or a change in perception about the way they play. Not paying as much attention to the news media about players' personal lives would go a long way toward lightening that pressure.
(iii) I firmly believe that Billie Jean King's victory in 1973 was a milestone for women; while it would likely have happened to some other woman at some other time, the fact that it happened to her was very important. As King herself was a very strong, independent and confident woman, she also forwarded an archetype of female strength that other women could use in their own Battle of the Sexes. If the King victory would have happened today in 2012, it likely would not have made as big an impact, particularly since the media has expanded greatly to the point where news stories often fall by the wayside or are drowned out by others.
(iv) I agree that the shift from second to third wave feminism is evident in the Nike commercial. The girls in the commercial clearly want to play; they know that they can participate on equal footing with a man. Furthermore, the girls know the benefits of allowing them to play (better confidence, higher self-esteem, greater chances of success), since they have seen the results from strong second-wave women doing the same thing. I sincerely hope that the audience for that commercial listened to their demands and let them play, since the girls were already confident and eager to show their worth.
(v) I believe that having strong, athletic female role models can go a long way toward showing that athletic women are just as attractive and worthy of legitimacy as feminine women. Demonstrating the need for physical fitness in schools is a good way to encourage the legitimacy of muscularity, as demonstrating strength as a positive attribute would show more girls that being muscular and athletic is a positive thing.
(vi) There are many things that PE teachers can do to make women feel more confident about their abilities and get them to participate in gym. Positive reinforcement of those girls who do participate and excel will show girls that they can be comfortable with their athleticism. Offering a comfortable environment that is free from judging, especially as women are starting out in their athletic careers, can go a long way toward letting them know it is okay to participate in gym.
(vii) For one, the incredible pressure that girls have to be "pretty" in order to be treated fairly or with any sort of positive attention in society needs to be lightened. Judgments must be lessened on the part of those who would expect a woman to be constantly attractive and wear makeup, etc. Having strong role models, again, who maintain their self-confidence in the face of being athletic or eschewing traditional female ideas of beauty can show other girls that it is okay. The toe-the-line behavior mentioned earlier is due to no women stepping forward and setting a trend; the existence of these role models can make being beautiful in their own way acceptable.
3. Reading the responses that I have seen on these issues, I believe that my opinions stay largely the same. I think that Billie Jean is a tremendous leader who paved the way for a lot of female athletes (and women in general) to blaze a trail in their respective pursuits, athletic or no. However, I do think that there are ways to help make homosexuality in athlete's personal lives a much easier thing to live with, as hard as that may be. Others also make a good point about the importance of Billie Jean's victory being that she beat a man.
I also agree that there are still many small steps to go towards achieving female equity in sports; despite the fact that Billie Jean beat a man, it did not change men's minds (or the world of sport) overnight. If anything, it has placed more pressure on women to be absolutely excellent in sport, because pressure has increased to be as good as Billie Jean. I also agree that Billie Jean King had more on her mind when guarding against her personal life than her homosexuality - others stated along with me that she had other obstacles to overcome; though I have a better idea of why the 1973 match was so important (as Riggs was a particularly telegenic bad guy for the reality-TV narrative of the game itself, saying such inflammatory things about women). The match itself became a grudge match, and that elevated it into a battle of the sexes rather than just a tennis match.
Reading some of the comments, I can see the appeal in having segregated PE classes for men and women in order to make women less self-conscious about the way they looked; however, I do not feel that further separation of the sexes will really make them more equal in each other's eyes, and holding off athletic competition between the sexes for later may make women and men alike less equipped for that eventuality.