How can I make boids move along a path? I'm making a flock of birds with boids.  I want them to move along a path. 

I tried curve guide, but they always move away from the curve.  If I make the particles Newtonian, then they follow the curve, but not boids. I want to use boids because I need them to be separate and flock reaching a goal.
Have an empty follow the curve.

For the boids set your empty as goal.