Jump ropes have probably advanced a bit since you were in elementary school. Most sporting good stores have a few models to choose from and there are also many online options as well. The first thing you need to know is how to size a jump rope. This is also what you may be told by salespeople but keep in mind that it is not set in stone.
Many ropes are now adjustable.
Beaded ropes have little plastic segments as opposed to one piece of material. This means that they weigh slightly more than traditional ropes. Most trick jump ropers choose beaded ropes because they handle very well. Beaded ropes are the best option for someone to learn the basics of jump-roping. The slight extra weight also adds a workout benefit, and the segments can be rotated, which makes them more durable than other ropes.