The most fundamental property of any pitch is its speed. In the graph below, the speed is shown on the vertical axis. Looking at pitches thrown by Zack Greinke of the Arizona Diamondbacks in a game against the Dodgers last year, we see that there are some leisurely ones (curveballs, denoted by pink symbols) and some electric ones (fastballs, marked by red and green symbols):
The arm swing and finish is the hardest thing to correct in a thrower besides having a feel for which finger the ball is coming off of through the throw. Lucky Baseball Rebellion has developed some fairly simple concepts to allow your child to efficiently enhance upper body mechanics and arm swing.  Here is a #TransformationTuesday tweet from Baseball Rebellion showing how a forty minute lesson can help your son or daughter with arm swing mechanics.

Another property of pitches is their break. Most commonly, that is the difference between their trajectory and that of a ball thrown with the same initial velocity, but no spin. As you may recall from earlier articles in this series, a basic fastball breaks up, while a basic curveball breaks down. A pitcher’s arm angle can modify these motions, so that a righthanded pitcher’s (RHP’s) fastball moves tends to move toward third base, as well as up.

There are several versions of the Slider, but we will illustrate the cut-fastball version (aka a “Cutter”) because it’s the easiest for most people to learn and throw. The Cutter is gripped similarly to a Two-Seam Fastball (index or middle finger along the Blitzball seam), except the two fingers should be closer together and the ball should be held with an off-center grip (towards the outside half of the ball).
I learned this pitching drill from Coach Scott Birchler who was a high school coach at our rival high school but as I got older and made the transition from player to coach, he helped me a lot. This pitching drill that he taught me is great for any pitcher who wants to be more consistent with their curveball or slider and fixes two of the biggest problems in guys who throw these pitches, dropping that elbow and not finishing the pitch.