Hello Kathleen,
The trick here is to structure your data in a way that CODAP can use to display multiple box plots.
So, if you have an attribute for, let’s say Group, and another, let’s call it Measurement, your data might look like this:
Group Measurement
before 7
after 5
before 10
after 9
etc.
The you put Measurement on one axis, and Group on the other.
Finally, in the Ruler menu for the graph click on the checkbox for Box Plot.
See the enclosed screenshot.
Hope this helps,
Bill