To answer the general question in this thread, the expectation of IQ test norming is that the item content of the test will be a surprise to the test-taker. Yes, there are definitely examples in various places (not just New York City in the United States) where children can become familiar with the test items either through formal prep courses or through playing various kinds of games. Of course, a vocabulary subtest is a part of almost all IQ batteries, and some children will have life experience of using the vocabulary that happens to be sampled on a particular test and some will not.
By contrast (I have another Gifted Issues thread in mind as I type this), part of the standardized conditions for administration of the SAT or ACT is that each test-taker receives a full sample test when registering for the test, so that each test-taker can in principle prepare in the same way by working through the sample test with actual test-taking time limits. Not doing that is to be a chump. I know a human intelligence researcher who argues that testing under that kind of condition, in which item content and format is disclosed to all test-takers, is actually a better test of intelligence than attempting to surprise all test-takers with items that may in fact be innocently familiar to some test-takers.
