Hi Cece welcome to Mac Eng
You mentioned you are interested in mechanical or eng physics, here are some useful links to look at:
McMaster faculty of Engineering:
http://www.eng.mcmaster.ca/
First year engineering courses:
http://registrar.mcmaster.ca /calen...13/pg1197.html
Department of Mechanical Engineering:
http://mech.mcmaster.ca/
Mechanical engineering courses:
http://registrar.mcmaster.ca /calen...12/pg1816.html
Department of Engineering Physics:
http://engphys.mcmaster.ca/
Engineering physics courses:
http://registrar.mcmaster.ca /calen...12/pg1785.html
McMaster Undergraduate Calendar 2012-2013:
http://registrar.mcmaster.ca /calen...12-13/pg3.html
Course selection:
http://registrar.mcmaster.ca /regis...%20Final. pdf
Reading course codes:
Lets take Math 1ZA3 as an example:
>> The 1 at the beginning means that its a first year course (2 would be for second year and so on...)
>> The 3 at the end states that its a 3 units course. All of your courses in first year engineering are 3 unit courses except for programming (1D04).
>> Later on in engineering some courses will be 4/5 units, its normal !
>> Math indicates that it's math course.
Mechanical engineering is a competitive program to get into in second year, so keep working hard in first year and try not to drop anything.
Take a look at this website:
http://www.eng.mcmaster.ca/eng1/requirements.html
Examples:
6.6 C.A. x 37 units = 244.2 points
6.6 C.A. x 31 units = 204.6 points
8.0 C.A. x 34 units = 272 points
You can see that if you drop/fail anything you will need to work extra hard to get into a competitive program like civil/mechanical. Also, don't listen to the website and do take the 2 electives in first year because if you don't then you will be down to 31 units and will need to work really hard to get into mechanical. The electives are not important for going into second year engineering, but they will raise your points to get into a competitive program in second year.
If you have a free choice, you don't need to worry about dropping courses, as long as you don't fail anything (because failing just 1 course means losing your free choice). Also, free choice doesn't include Elec&Biomedical, Chem&Bio eng, management.
Hopefully that helps