UTPA STEM/CBI Courses/Computer Science/Selection

Course Title: Computer Science I

Lecture Topic: Selection

Instructor: Laura Grabowski

Institution: UTPA

Backwards Design

Course Objectives

Primary Objectives- By the next class period students will be able to:
- Understand concepts of how selection structures work: Test current condition (while program executes), outcome of test, decision based on outcome
- Understand how different selection structures work (if, if/else, nested if/else, switch)
- Write C++ code for different selection structures

Sub Objectives- The objectives will require that students be able to:
- Write logical and relational expressions
- Identify syntax errors in selection statements

Difficulties- Students may have difficulty:
- Understanding the underlying concepts involved
- Remembering the correct syntax for the conditional expressions

Real-World Contexts- The concepts of decision-making are grounded in the real world -- we do it all the time. The details of this lesson, however, relate specifically to the context of learning how to design and write computer programs. In that context, some interesting applications include:
- Designing video games
- Comparison-based searching and sorting algorithms

Model of Knowledge

Concept Map
- Analysis of problem, requires
  - Critical thinking skills
  - Summarizing skills
- Design of solution (algorithm design), requires
  - Problem decomposition skills
  - Understanding of underlying programming concepts
    - Data types
    - Sequence
    - Control structures
      - Selection -- this lesson
      - Repetition
    - Modular programming (functions)
    - Arrays
    - Abstract data types
      - Structures
      - Classes
    - Pointers
    - Data structures and algorithms
      - Trees
      - Searching
      - Sorting
  - Use of design tools -- pseudo-code writing skills
- Implementation of solution
  - Tools of the trade
    - Learned in Lectures through
      - Slides
      - Analogies
      - Sample programs
      - Group exercises
    - Using C++ to implement underlying concepts (listed above)
    - Applying underlying concepts, covered in lectures using
      - In-class exercises
      - Lab assignments
      - Homework assignments

Content Priorities
- Enduring Understanding
  - Understand fundamental programming concepts
  - Understand basics of algorithm design
  - Be able to design, write, debug, and test simple programs in C++
- Important to Know and Do
  - Familiarity with programming environments such as Microsoft Visual C++
  - Document algorithm design with tools such as pseudo-code and flow diagrams
- Worth Being Familiar with
  - Time management

Assessment of Learning

Formative Assessment
- In Class (groups)
  - Pre-lesson quiz after student has read chapter.
  - Team coding exercises: Work with the group to write code for selection statements.
  - Code traces. Walk though code fragments provided and determine how statements will execute based on differing conditions at run-time.
- Homework (individual)
  - Lab assignments using selection
  - Worksheet: writing selection code fragments, executing code traces
Summative Assessment
- Unit quiz
- Exam

Legacy Cycle

OBJECTIVE

By the next class period students will be able to:

Understand concepts of selection structures: Test current condition (while program executes), outcome of test, decision based on outcome
Understand how different selection structures work (if, if/else, nested if/else, switch)
Write C++ code for different selection structures

The objectives will require that students be able to:

Write logical and relational expressions
Identify syntax errors in selection statements

THE CHALLENGE

You want to enter a game programming contest. You need to write a program to play the game “Rock-Paper-Scissors”. To win the contest, your game must be able to beat a human player in at least five out of ten consecutive games. How can you make your program win the contest?

GENERATE IDEAS

Play several rounds of two-player “Rock-Paper-Scissors” with your group.
- Make sure everyone understands how the game works.
- Observe, record your ideas about, and then discuss:
  - What strategies did you try?
  - What strategies seem to win?
Think about and write down your ideas about how you might write an algorithm to implement the game (individually).
Discuss your algorithm ideas with your group.
Brainstorm on what you need to implement your algorithms in C++
- What do you know that you can use?
- What do you sort of remember but need to review or have more details on?
- What don’t you know that you need to know in order to solve the problem?

MULTIPLE PERSPECTIVES

From the group discussions, groups share with class
- What sorts of strategies do you need to implement to program the game?
- What do you know? What do you need to know to solve the problem?
Lecture on selection (if, if/else, nested if/else) to help students gain understanding of selection structures. Organizing question for the lecture is “What do we need to know in order to write our “Rock-Paper-Scissors” program?
- The rules of the game
- How to compare the players’ actions (relational and logical tests) and make decisions based on what is happening at program run-time (selection).

RESEARCH & REVISE

Students will work in groups to complete an exercise on writing code for simple selection statements.
Students will outline their ideas for the “Rock-Paper-Scissors” program.

TEST YOUR METTLE

Students will receive feedback on their exercise solutions and on their game program ideas. Students will be given a quiz at the beginning of the next class.

GO PUBLIC

Students will be able to answer the questions about how to make run-time decisions in a program. Students will also complete lab assignments and homework assignments that focus on using selection structures.

Pre-Lesson Quiz

For Questions 1-4, use the following declarations to evaluate the given expressions as TRUE or FALSE.

int x = 8;
int y = 15;
double myVal1 = 2.5;
double myVal2 = 5.8;

Test Your Mettle Quiz

	TRUE
	FALSE

	TRUE
	FALSE

	TRUE
	FALSE

	TRUE
	FALSE