Slime is one of my favourite things, and I am delighted that I have a unit which requires me to make it this year. Fear Factor is going to be an awesome unit, I can tell already. The cleaners are going to kill me, though, for the amount of paint and glue and gloop we managed to get on the floor yesterday.
Anyway, it turns out that the high grade PVA we get here in NZ is not the same thing as Elmer's glue. Who knew? I am disappointed, because it means that our slime is not quite the same thing as I expected, based on the instructional video I found.
One of the things I like best about teaching science is that, if first we don't succeed, we can just try again. The lab technician and I spent a happy hour making various concoctions - sometimes, I am sure I didn't grow out of making mud pies, I am just more purposeful about it now. Anyway, we came up with two possible recipes:
40mL PVA glue
10 - 15 mL acrylic paint
approx 5g borax
Sprinkle the borax onto the glue and paint mix and mix thoroughly. If it is too sticky, try moving it to another person who has clean hands, or add more borax if that doesn't work
This gives a beautiful, shiny putty that is charmingly elastic and doesn't stick to your hands too much.
We also made a slime that is quite lightweight and frothy.
1/2 cup PVA glue
few drops of food colouring
1/2 cup water
2 heaped Tbs borax
Mix all ingredients in a tip top container. The PVA will curdle and the borax will feel grainy, but just keep mixing until it starts to coalesce. This will make a firm, frothy slime that sticks to your hands rather more than classic slime.
We plan to mix grated polystyrene into the second slime and make sculptures. We expect that they will set nicely if left on a windowsill for a couple of days.
Anyway, the science that we are teaching along with this is all about states of matter and things like that. I hope the students are learning something in addition to the enjoyment of slime. Next week, cornflour slime. I love me some non-newtonian fluids too.
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