The Wechsler Intelligence Scale for Children tests the IQ for children age 6 to 16 years of age. The test is composed of 16 separate smaller sub-tests that measure verbal, perceptual, memory, processing speed and executive function. Memory is tested through a basic knowledge of vocabulary and arithmetic, while processing speed is tested by having children recall patterns of codes. This test was one of the first IQ testing studies to experiment with the multiple choice testing format, and still uses it to this day.
The Stanford-Binet Intelligence Scale 5th Edition test measures the IQ of age groups 2-85. It was first developed in 1905, and has had several revisions since then. It specifically tests fluid and spatial reasoning, knowledge, quantitative reasoning, working memory, and visual-spatial processing and working memory. The test is organized through a system of three books, or test sections. The child being tested is given Book 1 first and then the difficulty level of each sequential part of the test is decided based on how the child scores in the prior section.
The Wechsler Preschool and Primary Scale of Intelligence Third Edition is another one of the popular studies designed by David Wechsler to test the aptitude of children. The Scale of Intelligence Third Edition measures verbal knowledge, reasoning performance, and processing speed. This test is specifically developed for children 2 years 6 months, 3 years 11 months, 4 years, and 7 years 3 months of age. The exact age of the child going through the testing dictates the percentile group his results will be measure against, as well as the depth and difficulty of the general information he is expected to know beforehand.
The Kaufman Assessment Battery for Children test is a study specifically designed for children age 3 through 18 and published by the American Guidance Service. For the most part, the test measures the child's mental capacity in relation to his motor functions and ability to reason. Such things as his ability to recite certain words in sequential word order, recall numbers, complete a story, and recognize faces are tested along with his knowledge of learned material like vocabulary and riddles.