CS21:Intro to Computer Science, Fall'08

(section 3, knerr)

Class Info | Schedule | Grading | Study Sessions | Style | Tips for Success | Integrity | Links


  • the optional Lab 13 is posted and due Thursday morning, December 18, at 10am


Welcome to CS21. This course will introduce fundamental ideas in computer science while also teaching you how to write computer programs. We will study algorithms for solving problems and implement solutions in the Python programming language. Python is an interpreted language that is known for its ease of use. We also introduce object-oriented programming and data structures. A deeper coverage of these topics will be presented in CS 35.

This course is appropriate for all students who want to learn how to write computer programs and think like computer scientists. It is the usual first course for computer science majors and minors. Students with advanced placement credit or extensive programming experience should place out of this course and instead begin with CS 33 or CS 35.

Goals for the course

By the end of the course, we hope that you will have developed the following skills:

Class info

Room: Science Center 240
Time: MWF 11:30am–12:20pm
Text: Python Programming: an Introduction to Computer Science by John Zelle
zelle book

Instructional Staff

Instructor: Jeff Knerr
Office: Science Center 238A
Phone: (610) 690-5758
Office hours: by appointment, or just drop by. Also see Weekly Lab Office Hours below.

Student Support: Betsy Horner
Office: Science Center 257
Phone: 610-957-6062

Student Mentors (Ninjas): Maria Kelly and Jake Baskin
Ninja sessions: Sunday and Wednesday nights from 7-9pm (see below)

Other Sections: Tia Newhall (MWF 9:30-10:20) and Andy Danner (TR 9:55am-11:10am)


1 Sep 01 Using Unix: Tue 8pm, Wed 7pm Introduction to Python and Unix
Chapt. 1-2

Assign: lab 0
Assign: lab 1
Sep 03  
Sep 05  
2 Sep 08   Numbers and Strings
Chapt. 3-4 (skip 4.6)

Assign: lab 2
Sep 10  
Sep 12 Add/Drop ends; QUIZ 1 PDF
3 Sep 15   Booleans
Chapt. 7

Assign: lab 3
Sep 17  
Sep 19  
4 Sep 22 Graphics Quick Reference Page Graphics, objects
Chapt. 5

Assign: lab 4
Sep 24  
Sep 26 QUIZ 2 PDF
5 Sep 29   Functions, objects
Chapt. 6

Assign: lab 5
Oct 01  
Oct 03  
6 Oct 06   Loops, Top Down Design
Chapt. 8, 9

Assign: lab 6
Oct 08  
Oct 10 QUIZ 3 PDF

Oct 13

Fall Break

Oct 15

Oct 17

7 Oct 20   Top Down Design, Loops
Chapt. 8, 9

Assign: lab 7
Oct 22  
Oct 24  
8 Oct 27   Searching, Analysis of Algorithms
Chapt. 13.1

Assign: lab 8
Oct 29  
Oct 31 QUIZ 4 PDF
9 Nov 03   Recursion, Sorting
Chapt. 13.2-13.3

Assign: lab 9
Nov 05  
Nov 07  
10 Nov 10   Dictionaries, Sorting
Chapt. 11.6

Assign: lab 10
Nov 12  
Nov 14 QUIZ 5 PDF
11 Nov 17   Defining new classes
Chapt. 10

Assign: lab 11
Nov 19  
Nov 21  
12 Nov 24   Object Oriented Design
Chapt. 12

Assign: lab 12
Nov 26  

Nov 28

Thanksgiving Break

13 Dec 01   Linked lists
Dec 03  
Assign: lab 13
Dec 05 QUIZ 6 PDF
14 Dec 08   Wrap-up
Assign: lab 13

Dec 19

Final Exam (2pm-5pm) room SciCntr 101


Grades will be weighted as follows:
40%Homework assignments
5%Class Participation
25%Final Exam

Homework policy

Programming assignments will typically be assigned in class at the beginning of the week and will be due before midnight the following Tuesday night. You are strongly encouraged to start early and to attend the study sessions for extra practice.

You will submit you assignments electronically using the handin21 program. You may submit your assignment multiple times, but each submission overwrites the previous one and only the final submission will be graded. Late assignments will not be accepted except in extreme situations and only if you contact me before the deadline. Even if you do not fully complete an assignment, you should submit what you have done to receive partial credit.

Weekly Lab Office Hours

CS21 faculty will staff part of our office hours in the robot lab (252 Science Center). Any CS21 student is welcome to attend any session.
Time Professor Location
Mondays 3:30-4:30 Newhall Science Center 252
Mondays 4:30-5:30 Danner Science Center 252
Fridays 2-3 Knerr Science Center 252

Study sessions

Several student mentors will assist us in class and run study sessions in the main lab (Science Center 240) on the following evenings.

Day Time Location
Sunday 7-9pm Sci Center 240
Wednesday 7-9pm Sci Center 240

You are invited and encouraged (free food) to participate in these study sessions (free food) to prepare for quizzes, to discuss programming concepts, and (free food) to get friendly assistance in working on homework assignments. Our CS mentoring team is dedicated to helping you learn to program in Python, while keeping your sense of humor intact. As an added bonus, free food is usually provided at the sessions.

Programming Style

Programming is not a dry mechanical process, but a form of art. Well written code has an aesthetic appeal while poor form can make other programmers and instructors cringe. Programming assignments will be graded based on style and correctness. Good programming practices usually include many of the following principles:

Also, look over the Python Code Style Guide for more details and some examples of good code style.

How to Succeed in CS 21

Academic Integrity

Academic honesty is required in all work you submit to be graded. With the exception of your lab partner on lab assignments, you may not submit work done with (or by) someone else, or examine or use work done by others to complete your own work. Your code should never be shared with anyone; you may not examine or use code belonging to someone else, nor may you let anyone else look at or make a copy of your code. This includes sharing solutions after the due date of the assignment.

All code you submit must be your own with the following permissible exceptions: code distributed in class, code found in the course text book, and code worked on with an assigned partner. In these cases, you should always include detailed comments that indicate on which parts of the assignment you received help, and what your sources were.

Discussing ideas and approaches to problems with others on a general level is fine (in fact, we encourage you to discuss general strategies with each other), but you should never read anyone else's code or let anyone else read your code. You may discuss assignment specifications and requirements with others in the class to be sure you understand the problem. In addition, you are allowed to work with others to help learn the course material. However, with the exception of your lab partner, you may not work with others on your assignments in any capacity.

"It is the opinion of the faculty that for an intentional first offense, failure in the course is normally appropriate. Suspension for a semester or deprivation of the degree in that year may also be appropriate when warranted by the seriousness of the offense." - Swarthmore College Bulletin (2008-2009, Section 7.1.2)

Please see me if there are any questions about what is permissible.

Links that are related to the course may be posted here. If you have suggestions for links, let me know.