Mount Teide - You can go most of the way up to the top of Mount Teide - Tenerife's active volcano - on a cable car. Click the link for details. If you are really adventurous, you can also apply for free to walk to the very top to the crater although access is limited. Application details are found through the link. It is a steep climb at altitude (11,500 feet) and freezing temperatures but is well worth the view at the very top. You can see Gran Canaria and La Gomera islands when skies are fairly clear and fantastic views around the island of Tenerife.
Karting Club Tenerife - located between the airport and Los Christianos just off the main motorway. This is a fun way for adults and children to spend a couple of hours driving around a racetrack on go karts.