Bathtub Soap Crayons




These bath crayons are easy to make, and most importantly, kids love them!  I used a bar of almond soap that was given to me around Christmas, but you can use any white bar soap as long as your kids don't have a skin reaction to it.

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Step 1: Ingredients and Supplies

To make these soaps, you need the following:

1 Cup of soap- any white bar you'd like

Food coloring

2 tablespoons warm water

Bowls- 1 for each color you want to make

Cheese grater

Molds- I used empty candy trays, but you could use ice cube trays, cookie cutters or even mold them with your hands if you'd like

Fork- for mashing it all together

Paper towels

Step 2: Grate the Soap

Grate your soap on the smaller side of your cheese grater. Since I was making a set each for my niece and nephew, I doubled the amount and grated 2 cups of soap, which was about half of a fairly large bar.

Step 3: Add Water and Mix/Mash

Add 2 tablespoons warm water for each cup of grated soap you have. It won't look like enough at first, but after you begin mixing, you'll notice it start to stiffen up and become thick. I find it easiest to mash the whole thing together with a fork rather than stir. Keep mixing until you have a thick, even consistency throughout and no soap gratings left.

Step 4: Separate and Color

Separate your soap evenly into as many bowls as you have colors to make. Use your food coloring to dye the soap. I started with 2 drops of coloring per bowl, then bumped it up to 4 each for brighter colors. If you're using the same fork to mix all of the colors, start with the lightest color first, wipe the fork off with a damp paper towel after that color is fully mixed, and move on to the next lightest color. This way, any residual coloring you have on the fork won't dirty your next color. Continue until all of your colors are mixed to your liking.

Step 5: Mold and Set

Firmly press your soaps into the molds that you've chosen. Pop them in the freezer for a couple of hours (or overnight) to solidify.

Step 6: Remove From Mold and Draw!

Remove your crayons from the molds. They're now ready to be used in the bathtub, so color away! Or, you know... give them to your kids.

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    19 Discussions


    3 years ago

    It's the soap that leaves a sticky residue on the skin. cheep soap without glycerin (they remove the glycerin to put in more expensive products like lotion.) Or if you have hard water, the soap builds up on the skin very quickly leaving you to feel sticky.


    Reply 8 years ago on Introduction

    I've never heard of it making people sticky. It's possible different brands might react oddly, but I just use the generic grocery store brand and it works without issues. Hope this helps!


    Reply 8 years ago on Introduction

    I haven't had problems with these staining, either. Just be sure you don't use copious amounts of food dye, and you should be fine.


    5 years ago on Step 6

    These are a great idea. Is it difficult to wash off of your tub?


    8 years ago on Introduction

    Hey mine got made into a featured article, but it isn't showing up on the front page. Can you help me since I noticed yours is on the front page.

    2 replies

    Reply 8 years ago on Introduction

    Hmmm... I'm still fairly new here and don't know a whole lot about the inner workings of Instructables. Maybe try asking in the forums? Someone there is bound to know. Hope you get it figured out!


    Reply 8 years ago on Introduction

    You have to wait until the entry deadline passes (Jan. 2). Then you can go to the contest page and vote for as many as you'd like while voting is open. Thanks for your interest!


    8 years ago on Introduction

    I remember having these when I was younger. I loved them. This is a cool idea.