This two day assignment starts off with the class reading the definition for an organelle, and then the teacher gives an example of an analogy for that organelle. Then the students share out one of two other analogies and the class writes them down. I occasionally mixed it up by having students share at their table, or get out of their seats and share an analogy with at least three other students.
The second day you might need to finish some organelles, but when you are done you can have the students get into small groups and add at least one other analogy per organelle. I also have students put stars next to the first 5 organelles since those are the ones focused on in the NGSS standard MS-LS1-2.
If I have extra time I have the students play a review game of password. Basically two students compete to guess the organelle while classmates give them analogies.
These notes include organelle definitions which are appropriate for a 6th grade level. I have also included a filled out version for you to see what the final product looks like. I do this lesson before we do the Cell Analogy Project.