The best prep for both Subject Tests (the one-hour, subject specific tests required by many top schools) and the more rigorous AP Exams (given in May, near the conclusion of each AP course) is a well-designed class and a good teacher. Sometimes students get lucky and need little extra prep because their class was so solid; MOST students, however, need to prepare for each Subject Test and AP Exam in much the same way they do for the SATs and ACTs, that is, by purchasing a book (or two or three) and learning material and taking practice tests. In the case of Subject Tests, students frequently have to learn one or several chapters worth of material (say, in Biology or U.S. History) that their teachers don’t cover in class for one reason or another.
Because most students take Subject Tests in May and June (to understand why, see my 2-min video, http://www.youtube.com/watch?v=m7rTrD9qHxY) and always take AP Exams in May, most parents go out and buy a prep book in April-ish. NOT A GOOD PLAN. For two reasons, a much better idea is to buy the prep book(s) at the very beginning of the school year: 1) the prep book(s) will help your kid get a better grade in the class–always remember grades are more important to admissions officers than test scores! I tell my students to prepare for tests in, say in World History, as if they had no prep book, and then the night before to study the corresponding chapter in whatever prep book their parents bought them, i.e., to reinforce key material and to fill in gaps. 2) When May rolls around and other students are panicked at the prospect of cracking open yet another book–at a time when final papers, big tests, projects, and…gulp…final exams are all on the radar screen–and consequently suffer partial to complete meltdowns, your kids will be REVIEWING material s/he’s been studying slowly and painlessly throughout the year. To summarize: buying the book in Sept rather than April = better grades in the class and higher scores on the test. No brainer.
For more great tips like this, you may wish to attend Dr. Yo’s popular 90-min parent seminar, “Secrets for Parents and Teens to WIN the College Admissions Game,” to be presented next August 22, 2013, 7:00-8:30PM ET in Glastonbury and ONLINE (details and tickets) and September 23, 7:00-8:30PM ET in West Hartford at King Philip Middle School, 100 King Philip Drive (details and tickets). 
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