So today I walked up to this girl I kind of new but not really and leaned against the locker beside her in a relax kind of way and I opened with, "So I need your opinion, I don't have much to do this weekend and I was wondering what movies you would recommend I check out?" At this point one of her friends jumped in, they both recommended maze runner after hearing what they said this third girl jumped in, I've seen her around my school but we never really talked.

Anyway at this point all three girls were facing me and I managed to keep the conversation going for a few more seconds, even girl number three pulled the books of the maze runner out of her locker and showed some interest toward the subject we were on and showing that she wanted to continue the conversation. I didn't know how to turn the conversation toward getting the third girls number or just continuing the conversation in general, so I just said "alright thanks" and walked away.

So I wanted to know, what I could have said or done to either make the conversation longer or try and change the subject toward me getting her number.

I'm still new to all this considering I got the game only a few days ago, I mean I'm fine with opening and my natural game is alright(but could still use some work) but it's changing the subject toward getting her number that I'm still having some trouble with.

Any advice toward phase-shifting the conversation toward her giving me her number would be amazing, or anything to help my natural game a little would be nice too.
thanks for the time.

Also I plan to try and get the third girls name and number after the weekend so any good openers would be great I was thinking maybe something toward the movie they suggested.