Blood Slime Model – What’s In Our Blood?
This blood model is the perfect way to discuss what is in our blood in a fun and hands-on way. Slime!

Blood Model with Slime
I love learning about science topics in fairly unconventional ways. Like when we learned about plant and animal cells with slime.
I knew then that I wanted to do a blood model with slime – I just had to wait for our human body theme.
And here it is!
We’re learning all about the circulatory system. And I think it’s vital that we cover the different parts of blood.
I feel like there are many misconceptions about blood, what blood does, what’s in blood, etc.
And making a hands-on model that appeals to kids is a great way to bring up these misconceptions easily. And then illustrate the reality.
Looking for a less slime-y way to make a model of blood? Try learning about blood with a blood model in a bottle!

What’s in Our Blood – the Slime Ingredients
The first step to making a blood model with slime is to collect the ingredients.
We just searched around the house to find items that would fit the parameters.
I didn’t want to go with food based items for this because I didn’t think the food would stay well in the slime.
However, there are some great candy and bean options when it comes to illustrating what’s in our blood.
I think this activity is particularly valuable when we get the kids talking about what can represent each part and why. It gets them really thinking about each part and the descriptions of each part.

Plasma
In this case, the slime is the plasma. That part has already been decided.
We made our glue clear but plasma usually has at least a slight yellow hint. You can add a drop or two of yellow food coloring to get that effect.
Red Blood Cells
Red blood cells make up 45% of our blood and they’re actually the reason our blood appears red. There are so many red blood cells that it makes all of our blood appear red. But the red blood cells are the only red part of the blood.
Red blood cells are responsible for carrying oxygen through the blood to all of the parts of the body and carrying carbon dioxide from all the parts of the body back to the lungs to be expelled.
They’re a little smaller than white blood cells but bigger than platelets.
We chose to use red perler beads for our red blood cells. They were the perfect size and we had enough of them to make our clear slime look reddish.
I wish we had added even more perler beads. I don’t think we managed to make 45% of our slime mixture perler beads.

White Blood Cells
White blood cells make up less than 1% of your blood – unless you’re battling an infection. The white blood cells are responsible for battling infections.
The white blood cell is not quite twice as big as the average red blood cell.
And since there are so few white blood cells in the blood, you only need a few pieces in your slime model.
We went with white pony beads.
They’re noticeably bigger than red blood cells and we had plenty of them to spare for our model.
We used 3 white pony beads for our model.

Platelets
Platelets make up less than 1% of blood volume but they’re no less important. Our platelets are responsible for clotting, like when we get a cut.
Interesting note – platelets are not actually cells but part of a cell.
Platelets are smaller than both white blood cells and red blood cells. They are usually yellow in color.
We used big glitter pieces for our platelet. Unfortunately, we didn’t have yellow so we used gold instead.
The glitter pieces were really rough and I thought they were perfect for representing platelets.

How to Make Your Slime
I wanted to have a really clear slime for this so I had to go with a borox recipe instead of liquid starch. I much prefer the liquid starch slime, but accuracy was important for this model.
There are many recipes for slime so feel free to use your favorite. But keep in mind the final product when you’re choose which method to go with.
Clear Borox Slime Recipe
For this recipe you’ll need:
- Clear glue (we used a 5oz bottle for ours)
- Borox (1/4 tsp)
- 1 cup of water split into two half cup portions.
Start by stirring 1/2 cup of water in with the 5oz of clear glue. Make sure it’s completely mixed together.
In a separate bowl, stir together the 1/4 tsp borox (yes, a very small amount) and 1/2 cup of water. If you use warm warm, the borox will mix in easier.
Next, pour the borox/water mixture into the glue/water mixture. And stir.
You should almost immediately see the slime come together.
When it gets too difficult to stir, it’s time to get messy.
Use your hands to continue to knead the slime. It’ll take a few minutes but i’ll come together all the way.
If it sticks to your hands at this point, wash your hands and remove all the sticky slime. Then you can go back to the slime and it shouldn’t be nearly as stick.

Make your Blood Slime Model
Now it’s time to mix in your blood parts.
Start with the red blood cells. Make sure to add a lot.
Fold in the pieces until they’re well mixed in.

Next add the white blood cells and fold in again.
Finally, add your platelets.
Now all that’s left is to play with the slime and point out all the different pieces!

This looks awesome!