This blog post has been contributed by Prab Singh who heads CollegeSource (http://thecollegesource.net/), an organisation that provides life coaching to adolescents and support to their family through the process of deciding their higher education and career goals.
No matter what you have heard about admissions in various countries around the world, the first and most important area that universities will focus on when reviewing your application will be your academic profile! You may be a virtuoso violinist, or a stellar artist, or the grandchild of a senator who is a major donor at that college, but if you cannot meet the standards of academic work that is expected at a particular college, they cannot accept you.
Rigorous Course Load: Within your academic profile, the first thing that they will try to assess is whether you have challenged yourself with the most rigorous choices available to you. They are viewing you within your academic environment, but are interested to see if you have stretched yourself. This does not necessarily mean that you have to do the highest level courses (though that is great), but that you have constantly pushed your own abilities. In general, they like to see a breadth of rigorous choices, but have high regard for courses in English, maths, sciences, second language and social sciences. Remember though that they will check for context, as it is in your context (that is, has the student continued to intensify the course choices over time?) and the context of the school (that is, there is no expectation that you should do Advanced Placement tests if your school does not offer them).
Pro Tip: Find out from your school counselor what courses a typically strong senior at your school takes. You don’t need to do the same courses, but that is the context that admissions will be looking at in your school.
Importance of Certain Courses: While the US is not usually adamant about specific courses, since the decision of a particular major can be decided later and you could do the required pre-requisite courses in the first couple years of college, some schools will have certain expectations if you are applying into a particular college within the university. For example, you may have a requirement of two Lab Science classes in many engineering schools. But the UK is a bit more particular about the specific course choices, so it would be prudent to see what courses are required by schools you are interested in for particular majors. Generally speaking, if between 9th and 12th grade you have taken 4 years of English, 3-4 years of math, 2-3 years of science (with lab), 2 years of social science and 2 years of second language, you will look good to all colleges.