As Burnsy said the course content can vary depending on your college. There appears to be a pool of 'units' which your college chooses from. There's also different types of BTEC National Diploma IT Practitioners - Software development, Systems support...etc
I'll give you a brief overview of the units I did during my first year in BTEC: Software Development.
Year 1:
Language and Communications: This unit really didn't appear to have much relevance at all to the subject of computing. Basically, we learnt about different types of language and documents used in business.
Computer Systems: In this unit we learnt how the various hardware components inside a computer operate. We also learnt mathematics using various numbering systems such as binary, octal...etc - Converting decimal to binary/decimal to octal/binary to octal...etc...etc, adding/multiplying/subtracting binary numbers...etc...etc
We also did a little practical work assembling/disassembling hardware and some programming using Assembly (A low level programming language)
Business Information Systems: In this unit we learnt how businesses and organisations operate, the different types of business, the structure of businesses and the functional areas of businesses.
Introduction to Software Development: This unit gave us an introduction to the programming world. The language which you use will vary depending on your college. We used Pascal, which is strange because it's rarely used in the industry these days, and is considered obsolete. According to my college, it's simple and logical in comparison to C/C++, therefore making it easier to understand at an introductory level.
At the level we were programming, C/C++ which are industry standard programming languages, barely differ to Pascal. It's more likely our college didn't have a member of staff availiable that had a knowledge of C/C++.
Anyway rant over, yeah, basically this unit was an introduction to programming. It's all pretty basic stuff, writing simple console applications, learning about variables, loops, functions/procedures, basic programming terminology...etc
System Analysis and Design: In this unit we learnt about the various stages of system development, the different levels of a system, the system life cycle, how to produce various documentation - Cost benefit analysis, feasibility study, data flow diagrams...etc
Human-Computer Interface: In this unit we learnt about the various components of a computer interface, both at a hardware and software level. We learnt how to design and implement an interface to meet the needs of a specific user or user group.
Software Applications: This unit was horrifically boring. Pretty basic stuff also. We learnt how to make use of word processing, spreadsheet and database software. (Microsoft Word, Excel and Access).
Operating Systems: In this unit we learnt about the history of operating systems, the different types of operating systems, the features of operating systems, how operating systems interface with the hardware components...etc
Website Development: In this unit we learnt how to produce websites from scratch using HTML, CSS and Javascript (written in Notepad) as well as how to use Macromedia Dreamweaver.
Any questions, feel free to ask. I'll do a similar write up of the units I'm currently doing in my second year later on/tomorrow.