Computer Science (ATAR): should I choose it?

What will I learn?

How will I be assessed?

Progression and companion subjects

No complete companion or exclusion review is attached to this profile. Check the official course-entry conditions, language eligibility and your school’s sequence before enrolling. Links between resource hubs show related learning; they do not establish a compulsory prerequisite.

Will I find it hard?

Difficulty depends on your experience, interests, teaching and assessment. These are our reflection prompts, not an official difficulty rating.

• Look at how much data, calculation and graph interpretation appear in the sample for this particular science.
• Can you explain the ideas in your own words as well as recall the terminology?
• Do investigations and evaluating evidence interest you? Check the course’s practical requirements.

Does it scale up or down?

Computer Science, 2025. TISC’s mean scaled scores summarise all students with a scaled score in the published course. The mean describes a cohort and gives no individual raw-to-scaled conversion. A scaled mean alone cannot establish whether this subject scaled up or down. Historical cohort data cannot predict your result or a future scaling direction.

Scaling is not a measure of difficulty or a guaranteed bonus. Prioritise content you can engage with and required subjects for courses you are considering.

Try a little of the subject

Programming

A computer stores every piece of data as a pattern of bits, and text is no exception. A character set gives each character a numeric code. The computer stores that code, and software turns it back into a symbol when the text is shown. In ASCII, the capital letter A is 65, lower-case a is 97 and the digit character '0' is 48. This is why the character '7' (code 55) is not the same thing as the number 7. Python makes the mapping visible: ord('A') gives 65 and chr(65) gives 'A'. Unicode extends the same idea to more than a million code points, aiming to cover all modern writing systems, most historic ones and symbols such as emoji. One value can be written in several number bases. Decimal (base 10) has place values 1, 10, 100 and so on. Binary (base 2) has place values 128, 64, 32, 16, 8, 4, 2, 1 across an 8-bit byte. Hexadecimal (base 16) uses the digits 0–9 and A–F, where A = 10 and F = 15. Each hex digit represents exactly four bits (a nibble), so a byte is always two hex digits. To convert binary to hex, split the byte into two nibbles and convert each one separately. Programmers like hex because it is short and maps cleanly onto binary. Every value in a program has a data type. An integer is a whole number, such as a count of tickets. A float holds a number with a fractional part, such as an average of 72.5. A string holds text, including codes like a postcode '6000' that are never used in arithmetic. A Boolean is True or False, such as whether a fee has been paid. In Python, input() always returns a string, so the value must be converted with int() or float() before any calculation. Operators act on values. Arithmetic operators are +, -, *, / and % (MOD, the remainder: 17 % 5 = 2). In Python, / always gives a float. Relational operators (==, !=, >, <, >=, &l

Original practice question: The character 'K' has the ASCII code 75 (decimal). What is this code in hexadecimal?

This is ATARMAxxing’s original sample learning material. It is not an official assessment task or a prediction of your school’s workload.

Explore the resources

Open the Computer Science (ATAR) subject hub and free preview (opens in a new tab)

• Computer Science — WACE Year 12 ATAR (opens in a new tab)

Core subject information and planning are free. Full study resources are optional.