Welcome to Extra Credit, Montgomery Extra's new column answering your questions about county schools. I'll start with just one question this week but will try to answer two or three a week in the future.

Dear Extra Credit:

Could you clarify the value of Advanced Placement and International Baccalaureate classes? It seems to me that many colleges are moving away from offering college credit for high AP scores. Is one program preferred by colleges over another? As more high schools push students to take AP classes or enroll in IB programs if available, where does this leave the student who is not very focused on academics? How can I as a parent understand the value of the courses, and how well they are taught, if students do not take the exams?

Alfie Rosenberger

Silver Spring

Some of our most selective colleges are raising the AP or IB score for which they will give course credit, but they have almost no research to back up these new rules. And often, the colleges back down when faced with a determined AP- or IB-trained student who wants to skip an introductory course.

Many colleges give placement tests the first week of freshman year to prove the worth of the AP or IB experience. Montgomery County students, being hardened veterans of every kind of test, usually do well.

AP and IB (college admissions offices have no preference) are the most useful part of the high school experience for college-bound students. If a student from this county wants to get into a selective college, he or she has to have AP or IB -- at least two test scores would be nice -- or a good explanation of why he or she doesn't. If a student wants to succeed at any college, having experienced the trauma of one of these college-level courses in high school is very valuable, according to a major federal study.

For the less academically inclined student, there are less conventional college-level courses and tests, such as AP music theory or IB theater arts. It is important for students to take not only the courses but also the final exams. Montgomery County schools, although not yet requiring the tests as is done in Fairfax County, are making it very difficult to avoid them.

Please send your questions -- along with your name, e-mail or postal address, and telephone number -- to Extra Credit, The Washington Post, 51 Monroe St., Suite 500, Rockville, Md. 20850. Or send e-mail to extracredit@washpost.com.