Practice tests are great, no question about that. But I would think it's kind of like baseball -- going to the cage everyday and taking lots of swings is a good thing in principle, but it isn't going to help all that much if you're just repeating the same old mistakes over and over.
Tutors and organizations that charge a lot of money are just placebo's IMO.My son worked with the published study guides and used the practice tests extensively, it is all about the effort you put in, there is no magic IMO just hard work and prep. What is really important is to start kids reading a lot when they are younger, turn off the TV and games, and force them to read a lot. Taking the timed tests over and over really prepared my son for the time constraints of the test. Some kids do better on the SAT and others the ACT, good advice to take both.
Not true. My son was a top student and went through the gifted program. In high school he took several AP courses. He did not excel at standardized tests. After having a tutor for six weeks his SAT score went from 1100 (Math & English) to 1270.
My son also went the private tutor route. He attended 10-12 one hour sessions at $100/hr. It's was easy to rationalize the cost when we considered the money spent on baseball. His overall scores went from 1500 to 1800 and helped to opened up many opportunities.