The student is holding on to a static generator, causing electrons to move from a concentrated area (the generator) to a less concentrated area (her body). The electrons seek refuge in her hair, causing repulsion of the individual hairs.

Here a student is holding a Tesla coil--what looks like a giant hypodermic needle. The end is purposely pointed in order to concentrate electrons--the repulsion gets them to leak out faster. On the way to the metal sphere of the electroscope, electrons excite air molecules. Electrons from those molecules jump to higher energy levels, and as they eventually fall back to lower levels, they emit light. (See feint blue "lightning bolt" in picture.) The electroscope becomes negatively charged, causing its thin leaves (gold-coloured) to repel. But the discharge of electrons is so intense that some electrons go right through the electroscope, as can be seen by another mini-lightning bolt at the bottom of the thin rod holding the gold leaves.

	Although a dry day, it's not a windy one. As the girl moves down the slide, friction causes electrons to either come off the plastic slide or off her clothes. In either case, each individual hair has an identical charge and the hairs try to get as far from each other as possible. Why hasn't my son gathered static? His hair might not be as dry, or his jeans don't gather static as easily as the fabric of my daughter's pants.
A balloon has been rubbed on my daughter's hair, either causing electrons to move from her hair to the balloon or vice-versa. Regardless of the details, the consequences will be identical. The balloon and hair are of opposite charge and the attractive electrostatic force acts over a distance. Since the individual hairs have the same charge, they also repel each other.

The best things in life are free: the chemistry of love and the love of chemistry.