Correlations between student discussion behavior, attitudes,

and learning

Gerd Kortemeyer

Michigan State University

AAPT 2007 Summer Meeting

Overview

• LearningOnline Network with CAPA (LON-CAPA)

• Online Homework

• Online Homework Discussions

• Online Homework Discussion Analysis

LON-CAPA• LON-CAPA is a free open-

source course management system, developed with a strong emphasis on science and math

• Used at over 50 high schools and over 40 university

• Shared content pool with over 275,000 resources

• Over 100,000 homework problems

• In addition: problem libraries for standard physics textbooks

4

• The problems are randomizing

• Every student gets a different version

Online Homework

Online Homework

• The problems can be quite simple …

Online Homework

• … or quite complex

Online Homework

• Different types

Online Homework

• Which type of homework do students profit from the most?

• Which kind of student profits the most from homework?

Homework Discussions• Student discussions are a

window into the thought processes of students

• Usually done by taping students working in groups, transcribing, analyzing Work intensive Often research setting, not

actual class work Small groups and sample sizes

Homework Discussion

• Discussion directly attached

Example Problem

• A bug that has a mass mb=4g walks from the center to the edge of a disk that is freely turning at 32rpm. The disk has a mass of md=11g. If the radius of the disk is R=29cm, what is the new rate of spinning in rpm?

“Expert” Solution

• No external torque, angular momentum is conserved

• Bug is small compared to disk, can be seen as point mass

€

1

2mdR

2 + mb02 ⎛

⎝ ⎜

⎞

⎠ ⎟ω0 =

1

2mdR

2 + mbR2 ⎛

⎝ ⎜

⎞

⎠ ⎟ω

⇒ ω =md

md + 2mbω0

What do Students Learn

• Almost all students got this problem correct in the end

• Did almost all students learn the concept?

• Did almost all students do what we expected from this problem?

Student Discussion• Student A: What is that bug doing on a disk? Boo to physics.

• Student B: OHH YEAH

ok this should work it worked for me

Moments of inertia that are important....

OK first the Inertia of the particle is mr^2

and of a disk is .5mr^2

OK and angular momentum is conserved

IW=IWo W=2pi/T

then do this

.5(mass of disk)(radius)^2(2*pi/T original)+ (mass of bug)

(radius of bug=0)^2= (.5(mass of disk)(radius)^2(2pi/T))+

(mass of bug)(radius of bug)^2(2*pi/T)

and solve for T

Student Discussion (cont.)• Student C: What is T exactly? And do I have to do anything to it to get

the final RPM?

• Student B: ok so T is the period... and apparently it works for some and not others.... try to cancel out some of the things that are found on both sides of the equation to get a better equation that has less numbers in it

• Student D: what did I do wrong?

This is what I did. initial inertia x initial angular velocity = final

inertia x final angular velocity. I=mr^2, angular velocity = w... so

my I initial was (10g)(24 cm^2) and w=28 rpm. The number

calculated was 161280 g *cm^2. Then I divided by final inertia to

solve for the final angular speed. I found final Inertia by

( 10g +2g)(24 cm^2)=6912. I then found the new angular speed to

be 23.3 rpm. This was wrong...what did I do incorrectly?

Student Discussion (cont.)[…]

• Student H: :sigh: Wow. So, many, little things, can go wrong in calculating this. Be careful.

[…]

• None of the students commented on Bug being point mass Result being independent of radius No unit conversions needed Several wondered about the “radius of the bug” Plug in numbers asap Nobody just posted the symbolic answer

• Lots of unnecessary pain

Quantitative Research• Classify student discussion contributions• Types:

Emotional Surface Procedural Conceptual

• Features: Unrelated Solution-Oriented Mathematical Physics

Classifying Discussions

Discussions from three introductory physics courses:

Classifying the Problems

• Classifying the problems by question type

• Multiple Choice (incl. Multiple Response) highest percentage of solution-oriented discussions

(“that one is right”) least number of physics discussions

• Ranking and click-on-image problems Physics discussions highest

• Problems with representation-translation (reading a graph, etc): slightly less procedural discussions more negative emotional discussion (complaints)

Degree of Difficulty

• Harder than 0.6: more pain, no gain

Good Students Discuss Better?

Correlations• Force Concept Inventory (FCI)• Pre- and Post-Test

Regression

• PostFCI=5,486+0,922•PreFCI+0,24 •PercentPhysics

• PostFCI=7,606+0,857•PreFCI-0.042 •PercentSolution

• Meaning what?

• Students who contribute 100% solution-oriented discussions on the average have 4.2 points (out of 30) less on the post-test, controlling for pre-test

Acknowledgements and Website

• Support provided by National Science Foundation Michigan State University The Alfred P. Sloan Foundation The Andrew W. Mellon Foundation Our partner universities

Visit us at http://www.lon-capa.org/