We loathe buying bags of ice in plastic and even that melts rather quickly, so we came up with what we think in a great idea. Take empty plastic containers - our local butter comes in the perfect, round size - and fill with water the night before. By morning, they are solid cubes of ice which I load into the cooler of drinks. Even today, after7 hours outdoors, there were still disks of ice remaining.
We take the leftover ice disks, toss them into the gardens to melt and trickle water the plants. We take the melted ice water and dump it into the flower pots. Trust me, this water is GREYWATER after dirty boys have had their hands in and out of the cooler all day. And, it means that a tired mom can squeak by without watering parts of the garden today!
So, if you have all sorts of weird plastic containers you can't bear to throw away, but are upset at yourself for buying, don't beat yourself up, they have a second use. And, if you have very thirsty boys, you will never be without a cold drink again!