[BUG] Which Way is North?

[Martin Jackson]

All,

I used Which Way is North? as an activity in class today.  I'm going 
to make an effort to report to BUG after using Bridge activities as a 
way of forcing myself to reflect on how each activity works.

This activity took place on the second day of a semester multivariate 
calculus course.  I allowed 30 minutes, which was ample.  I would say 
the activity is essentially foolproof (no better evidence for this 
than my use of it).  All seven groups drew the vectors for Problem 2 
(magnetic north) on a new plot giving me the chance to go around and 
pose the question "Is v the same vector in both plots?"  The 
Instructor's Guide suggestion of asking "How many libraries are 
there?" is perfect here.  I encouraged students to transfer their 
vectors from the second plot to the first.  One could encourage a 
single plot from the beginning either orally or by clarifying the 
written instructions.  I think this will work just fine either way.

Among other things, this activity helped me emphasize the idea that a 
vector is a single object.  We can describe it with a pair of numbers 
(after specifying a coordinate system) but the vector is not "two 
numbers" as some students might come to think of it.

Martin