You have just attained cult status!! You will be a hero to these kids. Have fun with them. There is no such thing as playing a position at this age. Wherever the ball is, that's where you'll find 20 enthusiastic children. (this does not include the goalies, although they sometimes even they join in the chase) Be prepared to be the on field medic as well as coach. At this age they seem to get run into and over alot when they're more interested in dirt, puddles, birds, butterflies, clouds, airplanes, waving to mom & dad and whatever else distracts them every second. Bandaids are magic, even if they're put on grass stains.
For them to accomplish dribbling is a successful season. Add in some good passing and scoring a goal will get you nominated for "Coach of the Year."
It gets a little frustrating at times but keep smiling. Words of encouragement, cheers, high fives, and buying ice cream after the game will already make you a winner in their eyes. You will be put up on a pedestal right next to their dads.
I have coached youth soccer from pre-kindergarten to sixteen year olds. This age is the most challenging BUT the most rewarding. You will see vast improvement by years' end. Thank you for volunteering to help our young ones Chopsticks.