NASA has launched a new website http://missionscience.nasa.gov/ for teenagers and kids, providing basic space information and also some high quality attractive space images. There are images from the Hubble and cool space animations. The website provides some spacecraft data to help student conduct experiments at school. The website also provides link to NASA Undergraduate Student Research Program (USRP) and the Summer-Internship related to space, and the information of where and how to apply for it. There is a games section for kids at this new NASA website.
Give it a try yourself as there is much more at http://missionscience.nasa.gov/.