PHP is a free, multi platform computer programming language. It is most used to develop dynamic web sites that are more than static HTML pages. The language is very easy to learn and use, and has an extensive list of add ons that allow it to do all kinds of stuff, from storing data in databases, pulling data from other web sites, sending emails, and more.

PHP is often used with MySQL, which is a free SQL Relational database.

In order to teach kids how to program, you need first to get them interested in something that is computer related. One of the best ways to get them interested in computers is games. They may want to write their own games, and that could be their entry into programming.

Here are some links to sites that deal with this subject.