Katy Perry's Firework (positive):I think Katy Perry's firework is posotive as she doesn't show much of her body in the video and is mainly wearing a dress. She also doesn't act seductive or sexual in the way that a stereo typical music video girl would normally e.g wearing seductive clothing.
Britney Spears' Toxic (Negative):
I think Britney Spears' video is negative because she is showing a lot of her body and acting very sexual to the men on the plane in the video. Furthermore she acts the same way as the stereotype of a music video girl,for example She is wearing very revealing clothes, she acts very seductive and sexual etc.
Katy Perry's California Gurls (Negative)
I think Katy Perry's California girls is negative because for the whole video there is nearly always a women in a bikini. Also Snoop Dogg is acting like a player of a game in control of the women's every move. This also may refer to the men being in control of the women and what they wear and how they act.
What you have here is solid and it has potential, you have picked your examples well.
T: What you must do now is develop your points and fully explain them using multiple specific examples. Pick out all of the technical aspects (Mise-en-scene, editing, lyrics etc)