Family Friendly: Fun and flowy, and can be taken at any pace.
As you ride down from the Calabasas Trailhead, take the first switchback to the left. The singletrack will end in a wide dirt road. Take the first right and continue straight ahead. The top of this trail is to the left and has a clear sign that says "Hustle & Flow" and the trail extends from Marker 7 to Marker 5.
The trail is composed of small jumps, rollers, and berms, all of which are optional for beginners. I recommend riding it with a bike that can pedal, as there is a flat section in the middle. At the end of the trail, you'll be faced with a somewhat strenuous but enjoyable climb out of the arroyo.