Please note courses are organized by levels. Generally level 1 is for 5-7 years old; level 2 for 8-11 years olds; level 3 for 12-14 year olds, level 4 for 15-17 year olds; level 5 for 18-25 year olds and level 6 for world class thinkers. For example Focus 420 would be for a 15-17 year old. Focus 440 (or any number after 420 would be courses on focus which should be taken after.