Jennifer,
We have about 700 students at our K-8 school. We have a small tumbler for our "Kinder Garden," but we built a 3 bin composter out of pallets in the main garden. Our kitchen staff gives us vegetable food scraps, and we compost a few hundred pounds every year.
If we were to go school-wide and capture all compostable material from breakfasts, lunches, and the kitchen, then I think we would need about 12 compost bins, and we would seriously need to consider using worms as well.
I would recommend not using hinges and latches if you build compost bins. Instead, design it so the gate lifts in and out.
Right now, our compost bins fertilize our garden and orchard, and it is a really cool process to show students.
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Ben Curtiss
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