Plant that produces legumes: Honey locust at Prairie Oaks Park. This bean pod is from a honey locust tree. It is a legume because it produces seeds inside of this pod.
Plant that produces flowers in a panicle: Goldenrod at Prairie Oaks Park. A panicle is showcased here in this goldenrod because of the branching characteristics in the inflorescence.
Plant in the Apiaceae family: Queen Anne’s Lace at Prairie Oaks Park. The defining characteristic that puts this plant in the Apiaceae family is the umbel shape of the inflorescence.
Plant in the Rosaceae family: Multiflora rose at Prairie Oaks Park. This plant is in the Rosaceae because of the hip fruit and serrate leaves.
Acer sacccharum: Found at Prairie Oaks Park. This plant is opposite and the leaves are palmately shaped/veined. 
Celtis occidentalis: Found at Prairie Oaks Park. The distinctive warty ridges of the bark give this plant away. The leaves were too high to see any galls, but the leaf shape was correct. The specimen is the tree on the left.
It’s nice to see that someone else went to a park for the scavenger hunt too! I usually go to Prairie Oaks to see birds, but it’ll be nice to be able to recognize some of the plants I see too. I also think it’s incredible that all of the scavenger hunt items can be present in a relatively small area if the habitat is right!
I didn’t know Queen Anne’s lace bloomed this late in the year!
I really like how your photo of the sugar maple clearly shows the opposite leaf pattern, one of the sugar maples most defining characteristics.
Honey locusts are one of my most hated trees- their seed pods smell pretty bad after being mowed, they can have huge thorns all over their trunk and branches that can be very dangerous, and they are very, very toxic to horses (and other animals too, I’m assuming). Yuck!