What are some early signs of schizophrenia? Things that will show up before someone is actually schizophrenic?

And at what age does schizophrenia usually start?

Below is a list of warning signs that suggest the onset of schizophrenia. It was developed by families who have a member with schizophrenia. Some of the behaviour is within the range of normal responses to situations. However, families felt that even with the mildest of symptoms there was a vague, yet distinct, awareness that the behaviour was "unusual".

Social withdrawal was observed by everyone. Most commented that their relative had been a "good person, never causing any trouble". Seldom had the person been socially "outgoing" during the formative years.

Excessive fatigue and sleepiness or an inability to sleep
Social withdrawal, isolation and reclusiveness
Deterioration of social relationships
Inability to concentrate or cope with minor problems
Apparent indifference, even in highly important situations
Dropping out of activities (skipping classes)
Decline in academic and athletic performance
Deterioration of personal hygiene; eccentric dress
Frequent moves or trips or long walks leading nowhere
Drug or alcohol abuse
Undue preoccupation with spiritual or religious matters
Bizarre behaviour
Inappropriate laughter
Strange posturing
Low tolerance to irritation
Excessive writing without apparent meaning
Inability to express emotion
Irrational statements
Peculiar use of words or language structure
Conversation that seems deep but is not logical or coherent
Staring; vagueness
Unusual sensitivity to stimuli (noise, light)
Forgetfulness
It is difficult to say at what age it really starts, it may start at a very younger age but may be hard to diagnose

usually 15-45, person hears sounds imaginary ones initially like a bell ringing, or clock ticking, then he hears voices initially of single person not talking to him later a disscussion of two people and later the voices command him, he feels controlled by them
it starts any time.
you can look up the clinical diagnosis on line through http://www.behavenet.com/capsules/disord...

it is not generally diagnosed in children and RARELY in teenagers because symptoms can closely resemble autism and they will rule everything else out before diagnosing someone under 18 with schizophrenia. This is an extremely serious mental illness and i would suggest if you have concerns about yourself or someone else they at the very least have a psychological exam or see a therapist for a consult.
Schizophrenia......... Well, there's alot of signs only problem is the signs are not always signs of schizophrenia.

A person may have split personalities
they may start having mood swings
start thinking someone or something is out to get them
have loud outbursts
cry alot
be depressed
start seeing things
start believeing that the world is one big conspriacy out to destory them
theres a lot but if you really want to know more go to the library and check out the medical books they have or go to your nearest college campus and ask a professor of psychology
checkout websites
try searching the web
Schizophrenia affects one percent of the population and can start at an early age, presents as early as 10 or 11.
Usual symptoms include Delusions (false beliefs that cannot be changed by facts and reality) Auditory Hallucinations (one or more voices or noises that you can hear that are not there) Other hallucinations can include Visual, Olfactory (smells) and gustatory (tastes) The latter two are unusual and often associated with Organic Brain Disease such as Tumours.
Laughing and talking to oneself without any overt source of stimuli. It is thought that Marijuana use in adolescents between the ages of 13 and 18 in the important brain formation phases could also contribute to Schizophrenia. Genetics and chemical imbalances in the brain are most likely contributing factors in combination with very high stress levels. Only clinically proven treatment is with Anti Psychotic Medications, ECT and illness education and awareness. Good luck. Seek professional help and guidance.