We planted our garden in pallets like this one (this is not ours, nothing is growing yet). We like how it keeps the plant in neat rows. Plus, the soil in Kekaha is not very good, so we filled ours with potting soil.
We also got a planter similar to this one. It is made out of a big plastic barrel that was cut in half. Ours is elevated with a wooden frame which is at nice height for the kids. Since it is off the ground it will be more protected from the chickens (which are everywhere).