Sound of Music costumes

I'm helping to sew costumes for a local high school's production of the Sound of Music this year. 

I'm specifically looking for good patterns for the childrens play clothes (the ones made from the curtains). 

Has anyone else done this?  What patterns did you use?  Thanks in advance!

Rachel

How fun!  If I remember the curtain costumes correctly (so great - 'Do you mean to tell me that my children have been running about Salzburg dressed in old curtains???') it seems like the a pattern for Dorothy's dress from The Wizard of Oz could be adapted.  I think the main things are that full skirt and puffed sleeves.  I think some of the children had entire dresses from curtains and perhaps the older girls had solid blouses with skirts and maybe a pinafore?