In the second video, a woman asks  a group of adolescents  to do a couple of activities like run and kick "like a girl" and they started to act like idiots as if  they had no force.
And then, the woman asks the same question  to a group of girls and they acted with force and like a real girl does it.
I think that the video shows to the people that the concept of "like a girl" is wrong and that the little girls starts to think that as a girl  they're weak. But they aren't, and in the end of the video says: "if run like a girl means win a race, I'll run like a girl".