matter on the bottom of the filter paper, fold the paper over the side of a jar so that the bottom of the strip is barely touching the rubbing alcohol. you can use scotch tape to secure the filter paper, if necessary.
leave the filter paper to absorb the color for 30-90 minutes. you should see small bands of color moving up the filter paper and separating out as they go. this takes between 30 and 90 minutes depending on conditions, so be patient!
once your kids have the technique, the rest is easy.
when the color seems like it’s moved as far as it’s going to go, lift the filter paper out 