What is the average IQ for a five year old?

Answer 1

My lay understanding of IQ tests is that 100 is considered the average, by clinicians, across age groups. I have also read that IQ scores can go up or down by, say 10 to 25, between testings and in different life stages. The conventional wisdom about IQ tests is that they measure generalized cognitive brain activity. For a typical individual free of brain disorders or brain injury, this "quotient" would not change very much no matter whether the subject was 5 years old or 75.