I like my milk tye-dyed

I felt like I had nothing to write tonight.  But… then I remembered that this past week in Grade 2 Science has been the most fun I’ve ever had teaching, and I think I’ll do a strictly teaching post today.

We’ve been learning about really great things — viscosity, transparency, absorption, dissolving, saturation…. it’s been great.

We started off mixing water and vegetable oil.  I coloured the water with food colouring so they’d get the full effect…

Then, for kicks, we made a lava lamp.  I love teaching grade 1 and 2 because every experiment just blows the lid off their world, because they didn’t know this stuff was possible before!  air bubbles in vegetable oil just makes them lose their minds.  All I hear around the classrooms some days are “whoa!”  and “oh my gosh!  look!”  It’s the most rewarding feeling EVER and I think I want to teach science for a really long time.

Yesterday, we dissolved different solids in water — sugar, salt, sugar cubes, sand (didn’t dissolve), flour, corn starch, a rock (didn’t dissolve), a nickel (didn’t dissolve), and my favourite — a jolly rancher lollipop.  That one took overnight to dissolve, and my kids talked me into trying to drink it…. I will never listen to them again.

My favourite part of yesterday was while we were learning what saturation is (adding solids to the point where no more solids will mix into the water), and we made a highly concentrated salt water mixture….. I let two of them taste it… one before it was fully saturated, and another as salt was settling on the bottom.  The looks on their faces were priiiiceless.  Priceless.  I don’t even have words.

But today was my absolute favourite.  We tye-dyed milk today.  I had those kids’ full attention for an hour straight.


Procedure (for those who want to try this.  It’s really cool!):

1.  Pour milk to the rim of a bowl (clearly I used an aluminum pie plate).
2.  Add several (I used 6-7) drops of food colouring of each colour.  Put them far enough away from each other that they don’t blend in together and change to secondary colours.
3.  Add 2-3 drops of dish soap.  The food colouring will flee to the edges of the dish as the surface tension of the milk breaks and the molecules can move more freely.
4.  I added about the same amount of food colouring again, again also keeping them separate.
5.  I added way more dish soap this time, swirling it in a circle as I went.  Because the surface tension of the milk is broken by the dish soap, the food colouring doesn’t mix together and you end up with tye-dyed swirls.

I took a video of this to post.  I was going to post it on YouTube and then link it to here… but to do that, I told my kids that no names were allowed to be mentioned and I couldn’t show any of their faces…. Of course, though, one of them said my name, and then I said his in response… haha… so it’s staying on my phone.  But you’ll have to try it for yourselves!  It’s easy, and it’s super fun!