R.F.
When my daughter was in Kindergarten, 1st, and 2nd grades, she would not leave the house for school unless her hair was "done". So, I got real creative, real quick. And, I'm not at all creative!! But, braids were my lifesaver!! One thing we did was Heidi braids. Make two low pigtails, just under and behind the ear; then just wrap each one over the side of the head just at or below the crown to the opposite ear. Pin to hold in place. Perhaps, you could add some flowers, ribbons or some such stuff to match the wedding colors.
Also, any kind of "fancy" braid is beautifil -- french, fishtail, reverse french, etc. I bought an inexpensive paperback book and just followed the instructions.
Good luck! I know how difficult it can be with straight hair that refuses to hold a curl. (BTW - as she grew, she became a ballerina and did many performances that called for curly hair - the fun just went on!! LOL!)
HTH,
R.