Any competent IT professional can list off a series of technologies that are heavily used in industry. However these are not necessarily the best solutions for the classroom. A range of factors including wow factor and inherent scaffolding are the key selection criteria.
A primary requirement is the teaching of quality IT behaviours. Technologies that break down disciplines such as indentation and commenting should be avoided. Equally technologies that are not robust but are portrayed as robust for example Microsoft Access. This will tend to cause the student to come acropper as soon as they leave school.
Another requirement is the level of scaffolding offered in the technology. Choosing a game development technology you could select many things from VB to C. However something like Flash and ActiveScript are an industry standard and provide very quick scaffolding to allow the student to deliver impressive (to them) results with little knowledge.
Care also needs to be taken in the broader socio-political context of IT. Ideally the student will gain a broad and deep experience of technology. Imperialistic products or companies such as Microsoft should be avoided since they tend to hide detail, extend standards reducing portability of skills and limit the student's experience.