That said, I love how this worked and how much Little Brother enjoyed it. It was a great sensory experience for him and he was all smiles with it this afternoon.
To begin with I purchased a box of 10 gallon ziplock bags a few weeks ago. I also used some foam shapes and colorful duck tape we had on hand. I added in a package of water gems. Water gems are water absorbent polymer beads which absorb and store water. They can be found in the floral department of your craft store. Although they are too small for infants and toddlers to play with, in this case they were contained inside the bag. I chose to use dry water gems.
I taped up the side edges of the bag for extra reinforcement and then put both the foam shapes and the dry water gems inside. Afterwards I taped part of the top but left a small opening for adding water.
I filled the bag with water by slipping it over the kitchen faucet. I didn't measure, just filled until it looked to be a good amount while taking into account the water gems were supposed to grow. I carefully squeezed as much air out as I could so that the bag was as flat as I could get it. In the end I needed to tape the bottom too, as it had an expandable bottom and it was holding too much air. I then taped across the top and the bag seal.
The gem directions said they would take a few hours to grow, but Little Brother was quite interested while watching me create the mat so I decided to let him try it out.
Tummy time first (which lead to some very interested sucking of the mat) . . .
followed by half-sitting studying . . .
and ending with some big smiles.
At first I was pretty disappointed in the gems, and thought if I made a mat again I wouldn't use them. As Big Brother woke up from his rest I put the mat into the bath tub to come back to later. When we did, I had a big surprise. The gems now looked much more like I had expected and very nicely filled out the bag. The squishy mat now felt a lot more interesting.
Of course now Big Brother had to try it and it captured his attention for quite a bit. He liked trying to move all the beads to one area.
He also enjoyed "helping" Little Brother explore the mat.
And after they went to bed? I found myself squishing it around with my toes too!