Thinkers Keys was originally written as a practical hands-on booklet, and sold in its   tens of 1000s around the world.  Recently, Tony has extensively rewritten it as a 21st century version,  and it is now available on a highly practical CD-Rom.  For the benefit of those who are new to Thinkers Keys, we have provided the  original version as a free download.  We also have provided a free demo of the new Thinkers Keys CD-Rom. (CLICK HERE TO REGISTER FOR THIS FREE DEMO) The Thinkers Keys CD-Rom is available for purchase as an 'Individual Licence' or as a 'Whole School Licence' (read more). *** A note for all of our Mac users ***  If you have recently upgraded to Mac OS 10.4.5 or above, and you are now   experiencing difficulties with your Thinkers Keys program, or you have  recently installed Thinkers Keys from CD-Rom onto your Mac OS 10.4.5  or above, please click on the free download below to upgrade your  version of Thinkers Keys.   ftp://download:dload@www.thinkerskeys.com/thinkerskeys/mac/Thinkers_Keys_Full_Upgrade.zip Instructions  1. This upgrade is for Mac / Apple only.  2. Download "Thinkers Keys Full Upgrade.zip" and save the file to a       location on your computer.   3. Double click the "Thinkers Keys Full Upgrade.zip".      A folder called "Thinkers Keys Full Upgrade" should      appear with a "Thinkers Keys Full.osx" file inside.  4. Replace the new "Thinkers Keys Full.osx" file over      your existing one (inside the previously installed      "Thinkers Keys Full" folder).