Here's and easy way to make the felted balls you need for that project. And it's great to do with kids. They love the "magic" that happens during the felting process and this technique contains the soapy water mess.
Get a small plastic container. Fluff your wool a little by pulling it apart. (You can use just one color of blend a few together)
Add a drop or two of dish soap that been watered down (50/50). But you really only need a drop or two or it will get way too soapy!
Also a little warm water from your tap. Then seal the container.
And shake.... and shake.... and shake. In all directions, side to side, up and down. Round and round.
When your wool ball feels firm and all the fibers have come together your done. Rise and let dry.
Once they are dry they are ready for felted acorns, or any other projects you can think of!
thanks to Mega Craft for the tutorial