Sensory bottles! They used Voss water bottles. Not sure where to find them but any water bottle will work. use mineral oil for a way to slow down the materials in the bottle. I usually do 2/3 water to 1/3 oil. Can also do just rice and small objects for I-Spy bottles.
Here is a healthy treat for your kids to take to their school Halloween party. Easy and inexpensive to make. Small water bottles wrapped in construction paper, with an Ocean Spray drink mix packet held on with a ribbon,