EBoard 05: Mental Models (Section 2)
Warning! You are being recorded (and transcribed) (provided the technology
is working correctly).
You should know the start-of-class algorithm
Approximate overview
- Administration
- Quiz notes
- Lab
Administrative stuff
Introductory Notes
- Please remember to return your blue cards to jar immediately after
determining where you are.
- During class, please work on our workstations, not your laptops.
- Congratulations to our football team for their season-opening victory!
Upcoming activities
Scholarly
- Thursday, 10 September 2026, 11:00 a.m.–noon, JRC 101.
Scholar’s Convocation: Ruth Feingold
- Thursday, 10 September 2026, 4:00–5:00 p.m., JRC 101.
The Department of Revenge (NY Times Reporter; four-time Pulitzer winner)
- Thursday, 10 September 2026, 4:15–5:00 p.m., Science 3821.
Study Away for CS Majors
- Refreshments in the CS commons at 4:00 p.m.
Artistic/Cultural
- Saturday, 12 September 2026, 8:00 p.m., Gardner.
The Spine Stealers and Babehoven.
Multicultural
- Friday, 11 September 2026, 4:00–6:00 p.m., Ward Field.
DEI Kickback.
- Friday, 11 September 2026, 4:10–5:00 p.m., HSSC N1170.
Middle of Everywhere (Taiwan)
Peer
Musical, theatric, sporting, academic, and similar events involving this
section’s students are welcome.
- Saturday, 12 September 2026, Grinnell Track.
Les Duke Invitational (Cross Country)
Wellness
- Wednesday, 9 September 2026, 6:30–8:00 p.m., Bear Dance Studio.
Brazilian Jiu-Jitsu
- Monday, 14 September 2026, 6:30–8:00 p.m., Bear Dance Studio.
Brazilian Jiu-Jitsu
- Monday, 14 September 2026, 8:00–9:00 p.m., Prayer Garage.
Meditation Group
- Tuesday, 15 September 2026, 4:30–6:00 p.m., Bear P103.
Wellness Yoga
Misc
- Wednesday, 9 September 2026, 8:00 p.m.–9:00 p.m., Noyce 3rd.
Mentor Session
- Thursday, 10 September 2026, 8:00 p.m.–9:00 p.m., Noyce 3rd.
Mentor Session
Other good things
These do not earn tokens, but are worth your consideration.
- Wednesday, 9 September 2026, 4:30–6:00 p.m., Springer Field.
Women’s Soccer vs. Coe
Upcoming work
- Due Thursday, 2026-09-10:
- On Friday, 2026-09-11:
- Quiz/LA on tracing (quite similar to the end of today’s lab)
- REDO Quiz/LA on decomposition.
- REDO Quiz/LA on procedures.
- Due Tuesday, 2026-09-15:
Administrative Q&A
What happens if I don’t finish a lab?
You should submit what you finish in class at the end of class.
I’d recommend that you read the rest of the lab and then attempt any
questions that seem difficult to you.
When can I make up an LA?
There are makeups every Friday. There are also extra makeup times
available. 7:30–8:00, 11:00–11:30, 4:00–4:30.
Do I have to do the makeup LAs this week if I missed them last week?
No. You could do them the following Friday. Or the Friday after.
Do I have to write reflections to earn a token for mentor sessions?
Yes.
What happens if I turn in a reflection more than 72 hours after the event?
I’ll be slower in grading it.
Did my lab partner turn in the lab and include me?
You can check on Gradescope. If you see an entry for your name, they did.
If not, they either didn’t turn it in or forgot to include you.
Note that the two of you should turn in the lab together at the end of
class.
Quiz notes: Decomposition
Key idea: Break a complex set of instructions into smaller parts and
name the parts.
Why? (TPS)
- Easier to understand [+2]
- For both you and for anyone you share the code with
- Smaller sections are easier to understand and test
- May help you limit mistakes [+1]
- You can check the sections one by one
- Perhaps you can “comment out” parts of them
- Avoids repetition [+1]
- Easier to change code; you can focus on the individual parts.
- May be more efficient; the computer does not need to recompute something
that use more than once.
Demo solution
Not included in eboard.
Grading notes
- Removing repeated code is important. If you did not remove repeated code
you likely got a Not-yet-sufficient.
- Good names are important.
- Need to decompose deeply.
Questions
What did you mean when you wrote “this is not a function”?
You used functions even though the instructions said not to.
(Marked Not-yet-satisfactory)
You treated a value as a function by putting parens around it.
(Small syntax error; did not affect grade.)
Quiz: Procedures
Key idea: Parameterize and name sets of code.
Why? (TPS)
- Helps us keep things organized - the names help
- Naming the parameters (and the corresponding vales) clarifies things.
“Ah, the 10 stands for the width.”
- Helps people read
- The name helps
- They don’t have to delve into the code itself to know what it does.
- Makes it easier to create multiple copies of something by calling on
it more than once.
- The (programmer who calls our code) gets to control some of the output
- Lets you easily build variants of the same thing
- E.g., a larger face, a different color tie
Demo solution
Not included in eboard.
Grading notes
- Whoops! That was way too much. I should have just done windows or
windows plus floor.
- If you got building plus windows as procedures, you got an S.
- In Scamper, you cannot nest
define statement.
Questions
Can we do local variables?
What’s a local variable?
You will learn eventually. For now, make do with what you have.
Will you post the code to the Web site?
No. I don’t like to keep answers to quizzes on the Web. However, I can
probably post it to teams.
Lab
Do the lab on Gradescope.
I’d encourage you to finish the lab on your own to prepare for Friday’s quiz.
For #6, f should be fun.