Every school will want something different.
I'll work around what you feel you need, after all it's your INSET, not mine...
Most schools benefit from looking at planning a dance lesson.
I often include a section on the skills you would hope to see.
Everyone asks about music for dance, so that's worth looking at.
I can also point you in the direction of other (free) resources.
We could look at dances from different times or cultures & how to develop the movements & ideas creatively.
Many schools like some help with keeping older boys engaged.
Looking at choreography is very popular.
Village schools or those working with vertically grouped systems may wish to look at working with different age groups.
Linking dance to literacy is one of my personal favourites - so many great stories! Also Science and dance is fantastic - I have a KS2 resource that covers all aspects of the science curriculum through dance.
Or we could look at a particular theme, recently I worked with a school who wanted to use the Olympics.