Admissions tests in private schools are supposed to measure your child's aptitude and readiness for the work in a serious private prep school. They are merely one tool for assessing a child's progress to date. Some children have learned their lessons well. Some children take tests well. Other children have deficiencies in certain skill areas. Still others do not test well.
Long-term Test Preparation
In a perfect world every child would master all the skills necessary to succeed academically. But children learn differently. Their teachers teach the same material differently. The school expects certain results in certain subject areas. That's why a standardized admissions test is a critical part of most private school admissions requirements.
If you can take the long term approach to admissions test preparation, it certainly is the ideal. But you need to start a few years out from the actual admissions test itself. Here's what to do: monitor your child's progress carefully. Identify any deficiencies and remediate them. Hire tutors if necessary. Create and maintain a climate for academic success. Set expectations accordingly.
Then about eighteen months before the admissions test date purchase the test preparation materials which are so widely available. Read about the test
your child will be taking. Understand what is required. Then have your child take at least 2 practice tests six months before the actual test date. That will give you enough time to tweak any parts of the test which require extra attention.
The Crash Course
Last minute cramming can pay off. Use this approach as a last resort. When do you use this approach? When you simply don't have the time to use the Long-term Test Preparation approach outlined above.
Cramming requires intensive, serious study. As much study as you can cram into the time available to you. Typically it will be the approach to take if you decide in eighth grade that your child simply has to go to private school for 10th grade. She will have to sit the SSAT exam in December of her ninth grade year. You don't have much time to waste. If you can, send her off to a good academic summer school, preferably at the private school you are thinking about sending her to. That accomplishes two things: makes her work hard and introduces her to the school. If she engratiates herself with the school's teachers and staff, it won't hurt her chances when she applies formally a few months later.
In addition to summer school, arrange extra help for the areas where she needs more work. Make sure that she works lots of practice tests so that she is not intimidated by the test experience itself. Good luck!