Colored Ice Sculptures - AKA Keeping Kids Busy

My kid's appetite for activity has been unquenchable these last 2 weeks, most likely because mom has not been at her best.  Usually they're content with one semi-exciting event per day, which will hold them off for hours leaving them to play happily amongst themselves or with each other.  But lately it's been a lot of "what's next, what are we doing today, now what?"  It's been exhausting and my creative well has run dry, and so the other day in between rain clouds I set them up with towers of ice in the yard and instructed them to go have at it.

Both kids remember this activity from preschool so for them much direction was unnecessary, but for you, my fellow moms, looking to occupy restless children for at least an hour, here's what you'll need.

Liquid watercolors or tinted water using food coloring (I really like Colorations Liquid Watercolors), rock salt of some sort like kosher or sea, blocks of frozen ice in various forms and sizes using tupperware containers.

The kids start by sprinkling the salt on the ice structure, as little or as much as they like.  The salt eats away cracks and divots into the ice, laying paths for the coloring to seep in.

And then they start pouring/squirting the coloring on the ice.  

The color will seep into the cracks the salt made in the ice, instead of just sliding right off.

The kids become fascinated seeing which way the colors will flow and 

what colors will meld together to form new colors.

I took pictures for the first 10 minutes or so, and then they stayed out there playing for another 45 minutes.  Ahh, the sound of happily occupied kids.  Nothing much better than that.

When they're all done just toss out on the grass or right into the sink for easy clean up.

Obviously this is a fun summer activity, but we found the fun to last even longer now in winter since the ice sculptures don't melt as quickly.  So that's what's been keeping my kids occupied for 1/12th of the day.  What's been keeping your kids busy these days?