Astronomy clicker question: helium fusion stars

Astronomy 210, Fall Semester 2008
Cuesta College, San Luis Obispo, CA

Students were asked the following clicker question (Classroom Performance System, einstruction.com) at the end of their learning cycle:

__________ stars will be able to fuse helium.
(A) Massive.
(B) Medium-mass.
(C) Low-mass.
(D) (More than one of the above choices.)
(E) (None of the above choices.)
(F) (I'm lost, and don't know how to answer this.)

Section 70160
(A) : 3 students
(B) : 8 students
(C) : 4 students
(D) : 10 students
(E) : 1 student
(F) : 1 student

This question was asked again after displaying the tallied results with the lack of consensus, with the following results. No comments were made by the instructor, in order to see if students were going to be able to discuss and determine the correct answer among themselves.

Section 70160
(A) : 1 student
(B) : 2 students
(C) : 0 students
(D) : 25 students
(E) : 0 students
(F) : 0 students

Correct answer: (D)

Low-mass stars (red dwarfs) will never get hot enough to fuse helium. Both medium mass and massive stars will eventually fuse helium in their giant and supergiant stages, respectively.

Clarification from one student who wanted all (A), (B), and (C) choices incorporated in his (D) reply: "I thought the question meant which stars make helium." (I.e., does "bake a cake" refer to making a cake from ingredients, or taking a finished cake and putting it into the oven?)

Pre- to post- peer-interaction gains:
pre-interaction correct = 37%
post-interaction correct = 89%
Hake (normalized) gain <g> = 83%