The Group X, Group Y or the Wrap roles can be used arrange multiple line plots vertically or horizontally. However, the different plots are not independent; they share axis settings among other.
Example:
dt = Open("$SAMPLE_DATA/Big Class.jmp");
dt << Graph Builder(
Show Control Panel(0),
Variables(X(:height), Y(:weight), Wrap(:age)),
Elements(Line(X, Y, Legend(5)))
);
//
For the the wrap role, the layout can be customized by right-clicking on the wrap variable and set e.g. "levels per row".