We love throwing theme playdates. Our Marching Band playdate was such a hit with the kids that I have to share it. We hosted it in the summer when real parades were happening. The kids really enjoy dramatic play, music and making crafts. As a craft we had them make their own drums and maracas After the craft, our little performers paraded around the house playing their instruments with some fun band music in the background. For the parade route we taped contact paper to the floor (sticky side up) so that their feet made music too! For the education component, we cut the contact paper into shapes. When the music stopped, the kids had to call out the shape they landed on.
For the drums, we used salt containers. They were only 33 cents each and small enough for the kids to handle. We saved the salt to make playdough for other playdates. Prior to the craft, I cut out several strips of scrapbooking paper for the kids to choose from. Then we cut out 2 thinner strips for the borders (see orange in pic). It was a simple tape/glue craft. We put out a bowl of stickers for the kids too. Make sure to cut off the bottom of the container. The drum beat sounds louder when the bottom is hollow.
For the drum sticks, just use some spoons in the house. The ones we made in the picture didn't work out so well. The simpler, the better.
You can also make some fun Maracas. Prior to the playdate fill the salt container with beans and seal the lid shut.