This unit test covers all of Big Idea 1: collaboration, program function and purpose, program design and development, and identifying and correcting errors.
Answer all 12 questions, then press Submit test. You will see your score, which questions you missed, and the correct answer with an explanation. Passing is 70%, the AP benchmark. You can retake it.
0 of 12 answered
Question 1 of 12Collaboration
A development team credits collaboration for catching a flaw that would have shipped if one person had worked alone. According to the AP CSP framework, what is the specific reason collaboration produced the better result?
Answer: D. Correct. Diverse perspectives surface problems and needs a single developer would miss, which is the tested benefit of collaboration.
Question 2 of 12Pair programming
During pair programming, one student types the code while the other watches, thinks ahead, and points out a likely error before it is even run. Which statement is correct?
Answer: B. Correct. Driver types, navigator reviews and looks ahead, and switching roles keeps both engaged and informed.
Question 3 of 12Function vs purpose
A weather app takes a ZIP code and displays the local forecast. Which pair correctly identifies the program's function and its purpose?
Answer: B. Correct. Function is what the program does (reads input, outputs a forecast); purpose is the need it addresses (planning around weather).
Question 4 of 12Inputs and outputs
Which of the following would the AP CSP framework classify as an INPUT to a program?
I. A user tapping a button on a touchscreen
II. A temperature reading from a sensor
III. A sound the program plays through a speaker
Answer: A. Correct. A button tap and a sensor reading are both inputs. Sound played through a speaker is an output, not an input.
Question 5 of 12Iterative design
A team builds a prototype, tests it with users, finds two confusing features, revises the design, and tests again. This best illustrates that program development is:
Answer: C. Correct. Investigating, prototyping, testing, and refining in repeated cycles is the iterative design process.
Question 6 of 12Requirements and users
Before writing code, a team interviews the people who will use the program and writes down what it must do. Why does the framework value this step?
Answer: D. Correct. Consulting users and recording requirements ensures the program is designed to meet real needs.
Question 7 of 12Documentation
Which statement about program documentation is most consistent with the AP CSP framework?
Answer: B. Correct. Ongoing documentation and comments help the team and future maintainers understand how the program works.
Question 8 of 12Error type
A program runs to completion but prints the wrong average because it divides by the number of items plus one. What type of error is this?
Answer: C. Correct. The program runs but produces an incorrect result, which is a logic error.
Question 9 of 12Error type
Consider this AP-style code:
total <- 0
FOR EACH price IN cart
{
total <- total + prices
}
DISPLAY(total)
Answer: A. Correct. The loop variable is price, but the body adds prices, so it references the wrong name. That mismatch prevents the intended total.
Question 10 of 12Testing
A team is testing a program that accepts a whole number of tickets from 1 to 10. Which set of test inputs best reflects good testing practice?
Answer: C. Correct. Good testing includes typical, boundary (1 and 10), and invalid (0, 11) inputs, especially edge cases.
Question 11 of 12Debugging
A program produces the wrong output and the cause is not obvious. Which debugging strategy is most directly aimed at finding WHERE the value first goes wrong?
Answer: D. Correct. Printing intermediate values (or hand-tracing) shows exactly where a value first becomes wrong.
Question 12 of 12Synthesis
Two teammates disagree about how a feature should behave. They discuss the trade-offs against the program's stated purpose and requirements, agree on an approach, and add a comment explaining the decision. Which combination of Big Idea 1 practices does this best demonstrate?
Answer: A. Correct. Resolving the disagreement by consensus, deciding against the purpose and requirements, and documenting the choice combines three BI1 practices.
Get in Touch
Whether you're a student, parent, or teacher — I'd love to hear from you.
Just want free AP CS resources?
Enter your email below and check the subscribe box — no message needed.
Students get daily practice questions and study tips. Teachers get curriculum resources and teaching strategies.
Typically responds within 24 hours
✓
Message Sent!
Thanks for reaching out. I'll get back to you within 24 hours.