Comparing Feedback Mechanisms inSapling Learning & Mastering Chemistry.

Question:Given a pressure and initial and final volumes, use w = -PΔV to calculate the work done by/on a system. Convert units from L.atm to J or kJ.

The calculation is simple, but students learning to work this problem might make several mistakes:

1. A failure to identify and convert units2. A mistake with the sign of the calculation.3. A mistake in significant figures

How do the two homework systems compare in feedback and format? Which is easier to use?

Avoid the straw man argument.

Any company can compare an excellent question from their system with a weaker question from another. Professors should consider working several comparable problems for themselves, to really evaluate which system is easier to use.

A Question in Sapling Learning

1. A screenshot of the question.

Sapling Learning

1. Student correctly calculates PΔV in Lˑatm, but does not convert to kJ. Feedback appears within the window.

2. Let’s Try Again.

Sapling Learning

3. Student converts from Lˑatmto Joules, but fails to convert to kJ.

Sapling Learning

4. Feedback prompts student to go to kJ.

Sapling Learning

5. Student converts to kJ, but gets sign backward. Again, feedback appears.

Sapling Learning

5. Student gets answer correct.

A similar question in Mastering Chemistry

1. A screenshot of the question.

A screenshot of the question –cropped for better visibility.(Remainder of question:“…from a volume of 0.130 liters to 0.500 liters.”)

Mastering Chemistry

2. The student first uses w = -PΔV, and correctly reaches an answer inunits of L.atm . This information is entered.

Mastering Chemistry

3. Student receives “Incorrect” Feedback, and message about units. Which units are needed?

Mastering Chemistry

1. Not sure which units to use, the student looks under “Hints” tab.

Mastering Chemistry

4. “Hints” tab is a pop-up window.5. Student clicks “Hint 1”

6. After clicking Hint 1, the following feedback pops up. The student just lost points, but still is not sure what units to use.

Mastering Chemistry

7. The student closes the hints window, and looks for more information in the “my answers” tab.

Mastering Chemistry

8. A new window appears, giving a list of answers given so far.

Mastering Chemistry

9. The student closes the My Answers window, and moves to the help menu to see about recognized units.

10. The help menu.11. Oh, here is the list of units.

12. Lets see…I need units for energy and work

13. After clicking “Energy and work”, the selection expands. Liters.atm is not listed. Which unit should I use?

Mastering Chemistry

14. Let’s look at the question one more time…

15. Oh, maybe they want the answer in Joules.

16. The student correctly converts from L.atmto Joules.

17. The student remembers to include a minus sign, since it was an expansion.

18. Student puts in answer…

19. Bizarrely, the help-menu pops back up as soon as the student hits submit.

20. After closing the help menu, the student sees that the question is counted correct, and difference in significant figures is noted.

Conclusions

While systems may offer similar features, Sapling’s extensive in-window feedback provides a much less stressful, easy-to-follow feedback mechanism.

Ultimately, students learn by working problems. The less time students spend navigating help menus and searching for information, the more time they can spend working problems.