Bringing or building musical instruments outside can be a great way for children to practice coordination, creativity, rhythms, and tones in a setting that allows them to create a great range of auditory experiences.
To deepen children’s thinking, encourage them to hit different parts of their drum with the stick to see if the sound changes; note when they make louder/softer sounds, and how the achieved it; and help them to create and test hypotheses about how changing their instrument will change the effect (i.e. what would happen if you put a leaf on your drum, and hit that with the drum stick?). By exploring these different traits of the music they create, children are learning about differences in tone and volume, two important concepts within musicianship. As they drum and dance, they are also practicing bilateral coordination (moving both sides of their bodies at the same time), a big skill for pre-writing.
Your instruments don’t need to be complicated. Some boxes and sticks can go a long way! Consider also including recycled cans (with sharp edges covered!), making shakers from water bottles and beads, or wooden spoons —see LOTS more ideas for a variety of ages here.