Why would you try to add a forkball before adding a slider if you are in late highschool ball? :?:
To really throw a forkball well you need long strong fingers. You wedge it in so that your index and middle finger are on both sides, and when your arm comes forward,you snap your wrist downward creating a ball that is either dead or tumbles slightly with a little overpin. The pitch takes a nasty dip when it arrives at he plate, but then again so should your curveball. This pitch can be hard to control, again why not the slider?