We learned that we don't care for ivory soap. We had it just biding time on a shelf in the bathroom. Then our little girl threw it in the bathtub, package and all. I didn't throw it out. So how about making bath crayons?
It's dead easy if you're not fussy about the look of the results. I do my creative stuff with a preschooler and a toddler, so I'm not fussy that way. It's not worth the grief.
Shred the soap. Ivory was the very brand my
recipe called for. We had a green variety, but it didn't seem to have a bad effect on the colors. I used my Kitchenaid stand mixer vegetable shredder to shred the soap. We did one cup at a time, and it takes a little more than one bar to make a cup.
Add warm water. Mix. I intended to use the stand mixer for this, but you know how small amounts don't work so well in mixers? Yeah. I wound up mushing it by hand instead. This is probably the cleanest thing I've kneaded in a while, but I chose to wear gloves. Make of that what you will. Have your little kid drop the colors in. That's a treat. My 4 year old calls this "colors" and has asked to do it again, several times.
Knead until it gets stiff. Then try to persuade it into molds. I didn't think it would come out of popsicle molds without the sticks (I should try that next time, with sticks), so I used ice cube trays. Repeat for all your colors. I didn't even clean the bowl between colors, and I'm satisfied with the results.
Chill in freezer 8 minutes. Pop out of molds and dry for 24 hours. I did the chill & dry step twice, because I didn't take it out of the molds the first time after freezing, and they don't dry well if you don't do that.
And they work! Yellow, although it's a favorite color around here, I can't recommend. It's not very visible on a white bathtub. But we wrote blue letters on the walls of the tub and sprayed them off with our bath squirters, so that was fun. It doesn't appear to have had a bad effect on the little gal's skin scratching problem either. I may not have to limit their use quite so much in future.