I believe that this type of question in the past has been answered by directing the person to Hoagie's where they have an article on test prep: http://www.hoagiesgifted.org/test_prep.htm

Generally, I'd venture to guess that most of us would suggest not prepping a child for ability tests b/c the goal is to get at what the child can do without practice. Of course, you don't want an anxious child, so going the route of what the Hoagie's article mentions in terms of trying to prepare the child for the experience of taking a test is probably a reasonable idea. Practicing questions of the sort on the test isn't generally recommended, though.

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