The Playdough Lab

 

I adapted this lab exercise from one that Paul Kelso at Lake Superior State University in Michigan does.  He introduced it to me at an "On the Cutting Edge" workshop held at Hamilton College in 2002.

 

Play-dough Recipe

Ingredients:

240 ml warm water* (or 1 cup)

360 ml salt (or 1.5 cups)

720 ml flour (or 3 cups)

70 ml cooking oil (or just over 1/4 cup)

food coloring

 

What to do with them:

Mix flour and salt in a large container.

Mix the oil, water* and food coloring in a smaller container.

Slowly add and mix liquid mixture into flour mixture.

Use hands to mix all materials together.**

Pour mixture onto a flour covered table and knead for about 5 minutes.

Add more flour if it's too sticky (may have to do this multiple times).

 

*Warm water is key. The warmer it is, the more likely the salt will actually dissolve and the playdough will have a smooth texture.

**It is easier to mix at home in a powerful mixer..... e.g., the stand kind with a 5 quart bowl made by Kitchen Aid (not how my mother envisioned me using it, I'm sure).

 

Here are the students' models:

The line drawn maps are from Davis & Reynolds, Figure A.15