First i love this offense makes it very easy to teach for my 12U girls basketball team. My question is how can we flow from the paul westhead fast break smoothly into the flex offense?

Coach -

I don't see why not. If you look at this explanation of the Westhead break, you'll see players end up in a 4 out 1 in set up and they are in the exact "flex spots".
http://www.breakthroughbasketball.com/offense/paul-westhead-fast-break-offense.html

If you don't have something immediately (post shot, lay up, jump shot) after your fast break, you are already in your flex spots and you can start the offense (if the ball is in the corner, you screen away... if the ball is passed guard to guard you run flex cut, etc, etc).

Don Kelbick has a transition offense products that goes over specific ways to transition directly into the flex or motion offense.
http://www.breakthroughbasketball.com/pr/Fast-break-transition-kelbick.html

Is this Justin from the football forums?

Yes Coach Rob it is I.

Jeff by the way love your compeitive drills video. I have one more question with the flex offense i only really saw 3 drills on the dvd is there more drills with the flex offense like a flex cut drill i think adding some more breakdown drills will help with kids first learning this offense

There are probably other drills but I have not run the flex exclusively so I'm not aware of others.

We do sometimes run flex 5 on 0 as a warm up / passing drill to get players learning the pattern and also improve passing, etc. Make the kids catch and pass in triple threat, meet pass, etc. You can call out certain options while their warming up too.

Beyond that just take a piece of the offense and use your imagination to turn it into a drills. So all your shooting and lay up drills include a piece of the flex offense.