"Under separation of church and state public school students are not supposed to be coached in systems of self identification; yet the students who are able to develop a self representation that is comprehensive of their real and potential participation in physical and social environments make the most of what public schools can offer: information on accessing technologies."
Bram's Translation for Katie:
"Under separation of church and state public school students are not supposed to be coached in systems of self identification;"
That means that schools are not supposed to tell you who you are in relation to the rest of society, or to the world (which could include a spiritual purpose or not) - they can only give you information which you have to "connect together yourself" (make a mind map with). It’s your job to use that information in order to locate yourself in space and time and culture and figure out what you could be up to when you become an adult.
"…yet the students who are able to develop a self representation that is comprehensive of their real and potential participation in physical and social environments make the most of what public schools can offer:"
This means that the students who are successfully creating a personal map of who they are, where they are, and what they are up to are the ones who can take the information public schools give and put it to best use.
"…information on accessing technologies."
This means that what schools do best is to give you starting points for different bodies of knowledge (History, Math, Biology, Literature, etc). They do that by teaching you how to read, how to talk about what you read, and how to deal with the kind of thinking required for various subjects. They also give you a framework - the basic information that you need to know to be able to pursue these subjects on your own. When you learn about the Revolutionary War, for example, you're usually using textbooks (an "accessing technology") to learn what the school system thinks is important about it (battles and the Founding Fathers, mostly), and you're also learning general information about the time period you can start with, though you may change it later.
You can’t really trust what the teacher tells you the Revolutionary War should mean TO YOU PERSONALLY – you’re only learning what the Revolutionary War is SUPPOSED to mean to children in your community who don’t/can’t go to private schools. However, you’re being taught how to read, how to use the library, and how to use the Internet. You can then choose to use these other "accessing technologies" to locate other information you find out on your own. To "round out" your picture of Revolutionary War America and what that period means for who you are and what you should be up to, for example, you could go online or to the library and find out what was going on with the Indians and the Slaves and the Women and the Poor, etc.. Then you can figure out which of those groups you identify with most and can learn the most from in your own position in life.