A cell zoo
The zoo keeper is obviously the golgi body, or the "mail room" of the cell, shipping materials off to different parts of the cell.
These might look like monkeys, but they're really mitochondrion, producing 90% of the cell's energy.
The carnivores, like the wolves and the lions and the alligators are the lysosomes, breaking down materials like food into smaller pieces.
There's a complete accompanying report that explains that the fencing is the cell wall, the lizards and snakes are the chloroplasts, the manager's office is the nucleus, the food storage barn is the vacuole, etc. etc.
I'm quite sure my 8th grade self would have made a poster.
The littles were completely enchanted.
And the big smile? Sister has promised them the zoo when it comes back from school.
An early Christmas.