Virtual Lab Ripple Tank Model & Real Ripple Tank Interference Model

1. Redesigning Pedagogy International Conference Thinking : Time for a Rethink? 4 Jun 2013, 10.30am to 12.00nn Symposium SYM001a NIE 7 01-TR706 Virtual Lab Ripple Tank Model & Real Ripple Tank Interference Model MrOngCheeWah (IJC), MrNg SooKok (IJC) Ms Lim Ai Phing (RVHS), MrLee Tat Leong (RVHS) Mr Wee Loo Kang (Senior Specialist) Education Technology Division, MOE

2. A Big thank you to OSP F. Esquembre, F-K Hwang, W. Christian, D. Brown ,M. Belloni, A. Cox, A. Duffy, T. Mzoughi ,, M. Gallis, T. Timberlake,  J. M. Aguirregabiria, W. Junkin, H. GouldJ. Tobochnik, Jose Sanchez,S. Tulejaand many more…. Digital Libraries http://www.compadre.org/OSP/ +500 http://www.phy.ntnu.edu.tw/ntnujava/index.php +2000 +65 computer models are already customized, work with AST on LCMS

3. Introduction to Open Source EJS • Actual Ripple Tank vs EJS Ripple Tank • Two independent action research projects – IJC and RVHS. • Methodology and Results • Expt groups which have access to EJS tend to perform better than their control group counterpart. • However, results are inconclusive as there may be other external factors • Evaluation and Student’s Feedback • Implication for self-directed learning and collaborative learning Proposed Order Static Display  Video Display  Simulation  Interactive

4. Conclusion • Responses were generally in favour of EJS but some felt that they were more comfortable with a teacher-guided approach in the learning process. • Both projects positively indicate the potential of using EJS in teaching and learning. EJS is but a tool. Designing the worksheets that is appropriate to their ability still poses a challenge. • The projects have made us more reflective in our quest to redesign pedagogy to cater to different ability groups and different learner (multiple intelligence)group. Proposed Order Redesigning Pedagogy How to design appropriate worksheets. To be more reflective on how to use simulation . To increase learning for different ability groups.

5. Many students have difficulty understanding waves and the principle of superposition. 1 • They held various alternative conceptions due to the abstract nature of the topic. 1 • This could be due to the lack of real-life experiences and the appropriate contextualization of the phenomenon.2 • The time varying dynamic nature of waves makes the topic more difficult to conceptualise. 3 1. Introduction 1Coetze & Imenda (2012) 2Dede, Slazman, Loftin & Sprague (1999) 3Chabay & Sherwood (2006)

6. The classic Ripple Tank Apparatus 1. Introduction The ripple tank has traditionally been used to teach superposition of waves (or interference).

7. The classic Ripple Tank Apparatus 1. Introduction Limitation Difficulty in manipulating the variables. Difficulty in viewing and tracking the spatial changes as it happens. Bulky and cumbersome

8. 1. Introduction Which clip shows the two wave sources to be in phase? Which clip shows the two wave sources to be in antiphase? Hint : There are two tell tale signs.

9. The Virtual Laboratory Ripple Tank Interference Model (Easy Java Simulation) • http://www.phy.ntnu.edu.tw/ntnujava/index.php?topic=2067.0 • It was developed to cater to the demands of the A-level syllabus. • Comes complete with graphs and displacements bars. • Attempts to stimulate real time interaction between two waves • Advantage : It has visual and interactive application 1 Introduction The Virtual Laboratory Ripple Tank Interference Model was developed by Andrew Duffy (2010)and by Fu-Kwun Hwang and Wee Loo Kang (2012).

10. Accessing the Ripple Tank Easy Java Simulation • http://weelookang.blogspot.sg/#!/p/physics-applets-virtual-lab.html • https://dl.dropbox.com/u/44365627/lookangEJSworkspace/export/ejs_Ripple_Tank_Interferencewee07try.jar

11. Phase difference = 180o Phase difference = 0

12. Easy Java Simulation (EJS) 1. Introduction The Virtual Laboratory Ripple Tank Interference Model was developed by Andrew Duffy (2010) and modified by Wee Loo Kang (ETD) (2012).

13. Easy Java Simulation (EJS)

14. Easy Java Simulation (EJS)

15. Easy Java Simulation (EJS)

16. 2 Method At Innova Junior College Timeline Expt Group did the EJS in a computer laboratory. Control Group observed a live demo on Ripple Tank

17. Pre-Test (Max Marks : 24) 2 Method The Pre-Test consisted of some MCQs and short structured questions to assess their understanding of the topic on Superposition.

18. Experimental Group 2 Method Experimental Group had a teacher to guide them through the worksheets on the uses of the various buttons.

19. Experimental Group 2 Method The Google doc. has Activities and Tutorial Questions which require them to use the EJS to find the answers.

20. Experimental Group 2 Method The students are required to write their reasoning in the spaces provided while using the EJS. They can give their comments after each activities.

21. Experimental Group 2 Method The EJS serves to encourage self-directed and collaborative learning.

22. Experimental Group 2 Method They can explore the 3D representation of the changes occurring during the wave superposition.

23. Experimental Group 2 Method By manipulating the variables, they can view the outcomes immediately. They can return to the website to explore further.

24. Trimmed to (Nexpt=53, Ncont=59) equivalent grouping of students with similar Pre Test Scores to see changes in Post Test Scores. 3 ResultsStand.Mean.Diff. Or Positive Effect Size. Expt Group had a better score from Control Grp by 4.0% Effect Size = +0.19

25. Assuming equivalent grouping of (Nexpt=53, Ncont=59) • The 4% outperformance (12% gain compared to 8%) and Standardised Mean Difference = 0.19 may be modest • But it does suggest the potential of learning activities involving students in guided inquiry using computer with Ripple Tank Interference Model to promote and deepen students’ understanding. 3 ResultsHake (1998)

26. Students survey (N = 42)

27. River Valley High School’s Approach

28. RVHS Approach • Online E-learning Module across the RV year 5 cohort • Premised on the effect that ‘the more times they used EJS, the better their exam scores.

29. Approach 2. The Superposition Tutorial was conducted with simulation (EJS) used by teacher to go through some tutorial questions. http://tinyurl.com/6Ktutorial

30. Approach Superposition Tutorial http://tinyurl.com/6Ktutorial

31. Evaluation (quantitative) • Pre-Test – 16 Past Year Multiple Choice Questions • Post-Test – 24 Past Year Multiple Choice Questions (Pre-Test with 7 added questions) • Test scores converted to % for comparison.

32. Evaluation (quantitative) • Question 24 in Post-Test: • On how many occasions have you used or seen others use the java applet (Ripple Tank Simulation) for e-learning? A 1 time (during e-learning) B 2 times (during e-learning, tutorial, etc) C 3 times D more than 3 times

33. results and learning (pre- & post- tests) • Analysis of variance (ANOVA) on pre- & post-test (N = no. of times student used applet)

34. results and learning (pre- & post- tests) • Analysis of variance (ANOVA) on pre- & post-test (N = no. of times student used applet) • Statistically significant difference between pre- and post- tests for all cases of N = 1 to 4.

35. Evaluation (qualitative) • Questionnaire to evaluate RVHS Ripple Tank Simulation lesson

36. results and learning (comments extracted from survey responses) • “The applet makes learning more visual thus making it easier to understand the topic of superposition. … we can explore the applet by ourselves and find out relations between the various variables.” • “strength is that we can go at our own pace …” • “for elearning, more active in learning as we are not fed with information but are actively exploring instead …”

37. Pros 1. It is visually appealing. 2. It is interactive, being able to see the changes in real time when the parameters are changed. 3. It is more engaging and able to sustain interest and learning. 4. The fact that they can carry out the simulation at their own pace for independent self-directed learning. 3 ResultsFocused Group Discussion among Expt Group (n=12)

38. Cons 1. The many buttons can be confusing. They are rather crammed and they had difficulty maneuvering the cursor. 2. The screen and font size are rather small. 3 ResultsFocused Group Discussion among Expt Group (n=12)

39. Conclusion • EJS does add a new and exciting dimension to the teaching and learning of Superposition. • The results though encouraging is not conclusive as there may be other factors. • EJS is but a tool. It is how we utilise it that brings to question of its relevance. • Catering to groups of multiple ability still posed a challenge. • Room for exploration.