Began discussion of  the cognitive growth and changes of adolescence.

Brain growth and development is greatest from conception to about age 3. Until relatively recently, it was believed that beyond this age, no new brain cells were produced and no further major structural development took place, but with the development of technologies for looking at the brain (MRI's, PET scans, etc) researchers have identified another 'growth spurt' in brain development in adolescence. Adults and older adolescents don't just think and know more than children and young adolescents, they think differently.

We briefly mentioned how social  settings affect this aspect of development for individuals growing up in a particular culture and then how individual factors affect a person's cognitive development in this stage.

3.  We listed some of the many  kinds of cognitive changes that may take place in adolescence: thinking becomes

• less 'concrete', more  abstract or 'formal', being able to think in symbolic terms. (Piaget) A child thinks that  you mean the color 'red' when you say that a newspaper is black, white and 'read' all over... and will argue with you that newspapers are only black and white! An adult or 'older' teen can think about concepts, not just realities.
• many-layered or multi-dimensional, able to operate on many levels at once rather than just focusing on one level of thinking. Now that newspaper can be both 'black and white' (coloring) and 'read all over' (what you do with the newspaper).
• more able to imagine possibilities and anticipate outcomes. ('What if...' and 'If this happens.....then that will occur..')
• more creative, able to combine what is know in new ways.
• more systematic in how cognitive tasks such as problem solving are approached.
• capable of thinking about oneself and  also seeing oneself from others' points of view. (This leads to the 'imaginary audience', in which the adolescent is not only self-conscious but thinks others are as overly aware of him as he is himself. Also this limited ability to 'inhabit' other people's actual point of view or experience means the adolescent experiences each new event or experience as if he/she is unique, the only person who ever had these feelings, these experiences. This is referred to as the 'personal fable'. Their individual experience of life up to that moment is all that is 'truly real', so, although they know that a lot of teenager are injured every year in driving accidents, it hasn't happened to them so it is not a real possibility. To some extent, both the 'personal fable' and the 'imaginary audience' are part of our thinking as adults, but never as strongly as when these experiences are new, in adolescence.) 
• more able to think about their own thinking process!  For instance, an adolescent might notice that he can speed up his computations in solving a geometry problem if he visualizes the geometric figure from a certain angle, or  might notice that focusing on thinking about a pleasant event while doing a boring task helps the time pass more quickly.
• can think in more flexible, relative terms. In childhood, 'facts' have a clarity and simplicity that the newly sophisticated adolescent mind rejects as too simple. This is particularly evident in their developing sense of moral judgement: what was 'wrong', always, no matter what the circumstances when they were children, becomes something which can be right under other circumstances.  (It is wrong to steal, but it is more wrong to let your baby starve to death when there is food available, even if you can only get it by stealing....)

Saw a Frontline Video on the development of the teenage brain and a short video clip on the conviction of the two boys, ages 13 and 14, of murdering their father and their sentence of 22 years to life in prison. In the light of what we just learned about the development of the brain in adolescence, should juveniles be tried in adult courts and given adult sentences? The current trend is to base this decision on the seriousness of the crime, not the developmental maturity of the child's ability to reason, to anticipate consequences, to control emotions, etc. (not to mention mitigating factors such as the fact that the children's inadequate parenting and  sexual abuse.