Here are the steps to my lesson:
1) Step 1: I start the lesson by reading these books . . .
2) Step 2: Then I asked the question . . .
3) Step 3: I took photos of each student with a plain background and airdropped my keynote project to the student's iPads.
4) Step 4: Students used Instant Alpha to take away the background of their picture.
5) Step 5: Students added their picture to these colored slides below . . .
6) Step 6: I provided these slides with animal parts.
7) Step 7: Students added animal parts to their picture. Here's the end result!
On a final note, there are some tricks to creating the isolated animal parts. I'm happy to share my project with you (just email me at email@example.com) but if you'd like to create your own animal parts, here's a screencast showing the steps: