I absolutely love this photo!  Everyone looks relaxed  – well, most everyone -and some are even quite playful, with two women holding balloons and another blowing up a balloon.  I particularly love that some of the women are wearing pants.  Unfortunately I can only identify one person, my grandmother Georgiana Frances Schenk (2nd from the left, with the jaunty black hat).

I think this may be a “class photo” – perhaps a high school graduating class.  If my guess is correct, the date would be about 1917 or 1918.  There are two older gentlemen in the center of the photo – perhaps they are teachers?  I believe th photo may have been taken in Marysville.