CS Teacher Ed Requires different goals and methods than CS Major (software professional developer) education. Talks about (a) what successful teachers know, (b) student misconceptions, and (c) about MediaComp as a model of non-major/non-developer intro CS.
Harvard Graduate School Education: teaching cs to teachers
1. CS TEACHER ED REQUIRES DIFFERENT
GOALS AND METHODS THAN CS MAJOR
EDUCATION
Mark Guzdial
April 8, 2015
2. CS Teachers need CS Content Knowledge:
But how?
1. CS Teachers need different knowledge and skills than
Software Developers.
2. CS classes designed for non-developers can be more
successful than those for CS majors.
If we are ever to have pre-service professional development for
CS teachers, they need their own CS classes.
3. #1: CS Teachers need different knowledge and
skills
3
What do our model CS teachers do and know?
Defining a Successful CS Teacher:
• Recruits more students into CS
• High pass rate
• Confident and satisfied with teaching CS
4. How do you prepare your students for
the AP CS exam?
4
“Everything in that class is more or less an
assessment. They’re supposed to read certain
sections in the book, and then they have quizzes
over the reading. After they do the reading
assignments, they have Gridworld case study
quizzes and also Gridworld case study segments of
code that they will go in and manipulate to change
to get the things in the Gridworld case study to react
different ways. Those are pretty much graded as
labs or programs or quizzes.”
5. How do you prepare your students for
the AP CS exam?
5
“Everything in that class is more or less an
assessment. They’re supposed to read certain
sections in the book, and then they have quizzes
over the reading. After they do the reading
assignments, they have Gridworld case study
quizzes and also Gridworld case study segments of
code that they will go in and manipulate to change
to get the things in the Gridworld case study to react
different ways. Those are pretty much graded as
labs or programs or quizzes.”
6. How do you prepare your students for
the AP CS exam?
6
And then if I read these [student quizzes], I can see any
misconceptions or gaps in what I’ve done. I get a picture in
my mind of where the current class is. Making them do the
explaining is new this year. I’m seeing them do a lot better
there. I‘ll do like little code (assignments) that they’ll write
once a week. They have to write it by hand away from the
computer, and I’ll read that and write them comments on
what they’re doing and help them grade it with a rubric, and
also pass them back after I’ve read them for them to grade,
too, and have them look at what was catching it or where it
didn’t quite get to it.
7. How do you prepare your students for
the AP CS exam?
7
And then if I read these [student quizzes], I can see any
misconceptions or gaps in what I’ve done. I get a picture in
my mind of where the current class is. Making them do the
explaining is new this year. I’m seeing them do a lot better
there. I‘ll do like little code (assignments) that they’ll write
once a week. They have to write it by hand away from the
computer, and I’ll read that and write them comments on
what they’re doing and help them grade it with a rubric, and
also pass them back after I’ve read them for them to grade,
too, and have them look at what was catching it or where it
didn’t quite get to it.
8. A successful CS teacher…
8
• Writes assignments and comments, not code.
• Guides students through rubrics, not syntax.
• Is interested in learning (coding away from the
computer, explaining), not productivity.
• Is not all that focused on assessment.
9. Students find developer-simple
things complex
9
• Brian Dorn found that end-user
programmers (CHI 2010) found
assignment difficult to learn.
• Dehnadi and Bornat tested
understanding of assignment to predict
CS1 success.
• The predicting variable was consistent use
of model of assignment.
10. Common Misconceptions about Assignment
10
• Assignment is a move.
• number1 is now empty.
• Assignment is a swap.
• Assignment is a relationship.
• If we later change number1,
number2 will automatically change.
number1 = 14
number2 = number1
11. Common Misconceptions about Assignment
11
• Assignment is a move.
• number1 is now empty.
• Assignment is a swap.
• Assignment is a relationship.
• If we later change number1,
number2 will automatically change.
number1 = 14
number2 = number1 This is not where
software
developers focus.
This is exactly
where teachers
focus.
12. #2: Domain-specific classes
Fall 1999:
All students at Georgia Tech must take a
course in computer science.
– Considered part of General Education, like mathematics,
social science, humanities…
1999-2003: Only one course met the
requirement.
– Shackelford’s pseudocode approach in 1999
– Later Scheme: How to Design Programs (MIT Press)
13. One-class CS1: Pass (A, B, or C) vs.
WDF (Withdrawal, D or F)
Success Rates in CS1 from Fall 1999 to
Spring 2002 (Overall: 78%)
Architecture 46.7%
Biology 64.4%
Economics 53.5%
History 46.5%
Management 48.5%
Public Policy 47.9%
14. Contextualized Computing Education
What’s going on?
– Research results: Computing is “tedious,
boring, irrelevant”
Since Spring 2003, Georgia Tech
teaches three introductory CS
courses.
– Based on Margolis and Fisher’s
“alternative paths”
Each course introduces computing using
a context (examples, homework
assignments, lecture discussion)
relevant to majors.
– Make computing relevant by teaching it
in terms of what computers are good for
(from the students’ perspective)
16. Asking women: What is CS to you?
MediaComp Traditional
Rich, Perry, Guzdial, SIGCSE 2004
17. 38
Survey One Year Later
19% of respondents had programmed since class
ended
"Did the class change how you interact with
computers?”
– 80% say “Yes”
– “Definitely makes me think of what is going on behind
the scenes of such programs like Photoshop and
Illustrator.”
– 'I understand technological concepts more easily now;
I am more willing and able to experience new things
with computers now’
– 'I have learned more about the big picture behind
computer science and programming. This has helped
me to figure out how to use programs that I've never
used before.’
18. Results:CS1“Media Computation”
86.470% 88.360% 84.710% 89.870% 91.940% 87.500%
80.330% 82.900% 77.460%
12.540% 10.270% 14.650% 9.370% 7.580% 11.410%
19.650% 17.100% 22.540%
Total
Fall03
Females
Fall03
Males
Fall03
Total
Sp04
Females
Sp04
Males
Sp04
Total
Fall04
Females
Fall04
Males
Fall04
WDF
Pass
Change in Success rates in CS1 “Media
Computation” from Spring 2003 to Fall 2005
(Overall 85%)
Architecture 46.7% 85.7%
Biology 64.4% 90.4%
Economics 54.5% 92.0%
History 46.5% 67.6%
Management 48.5% 87.8%
Public Policy 47.9% 85.4%
19. Summary:
• Successful CS teachers are different than software
developers.
• Different skills
• PCK
• Traditional CS classes tend to be focused on software
development.
• Classes that teach the CS specific to a particular group can
be successful: Retention and Longterm Usefulness.
19
20. Thanks!
Colleagues: Barbara Ericson, Tom McKlin,
Lijun Ni, Briana Morrison, & Brian Dorn
Our Funders:
US National Science Foundation
– Statewide BPC Alliance: Project “Georgia Computes!”
http://www.gacomputes.org
– Expanding Computing Education Pathways Alliance,
http://expandingcomputing.org
– CCLI and CPATH Grants, and now CE21 to produce new media
Georgia’s Department of Education
GVU Center, and Institute for People and
Technology (iPaT) at Georgia Tech