Amazon has this Set of 4 BPA Free Fit & Fresh Cool Coolers Slim Lunch Ice Packs for $7.99 with FREE Super Saver Shipping and $35 purchase or FREE with Amazon Prime.
These are so perfect for back to school lunches. Help keep all those healthy fresh foods nice and cool until lunchtime. And they are BPA free. Score.
They get GREAT reviews, too.
Pricing was current when the post was published, however Amazon prices change often, so please check before you buy.