This works well for a mixture of boys and girls. When my little girl was turing 4 we had a fishing party. I bought some inexpensive off white fabric and made little fishing vest. I printed out little pictures of bass fish, fishing poles, fishing hooks and each of the guest names on the iron on paper to decorate the vest. On the back I had a picture of my little girl holding a real fish. My husband had an little aluminum boat that we put next to the privacy fence in our back yard.  We used child sized character fishing poles with clothes pins on the end instead of hooks and had each of the kids cast the line over the fence while one of us was on the other side attaching a prize on the other end. To decide what order the kids went fishing, we had a big was tub full of water and rubber ducks with numbers on them. Each child got 3 cast and each prize was put into a ice chest they got to bring home.  (The little soft zipper ice chest) Or you could use little baskets. One of the prizes I used green foam sheets from the local art store and cut and glued into the shape of a fish and filled full of candy. So everyone was able to catch a Keeper Fish".  The other prizes were random depending if it were a boy or girl.  Sometimes the prize was put into a small rubber boot.( The boot was threw back over the fence.)  All the kids were able to sit in the boat while the other one was fishing and would take turns useing a wooden paddle to pretend they were rowing the boat.  The cake had a big bass on it and we had another desert called dirt cake in little aluminum buckets I found at the dollar store.  But can be found at craft stores too. The dirt cake was made with smashed oreo cookies and each had some gummy worms coming out of it.  And the guest got to bring the little buckets home with them as well. "