My son's school topic of animals had a focus on the Arctic and Antarctic, one suggestion was to make an igloo.
I remembered that at xmas I brought artificial snow .
We followed the instructions that were basically add water to the powder.
Soon we had a tub full of artificial snow.
We coloured the snow with food dye.
The tubs were ideal for snow castles : igloos.
They observed wind up penguins and how they moved on the snow.
The penguins were from crackers and are number which we used to race and add up. Identified odds and evens.
The snow lasted for well over 10 days. In the fridge and out of the fridge. I think it would last much longer.
We had something like this