Convert Clipart to Line Art
Whether you are creating a coloring sheet to print out or making a clipart image unique for the web, this tutorial is one you will find beneficial. For a sample image to use with this technique, I went to Microsoft Office and copied and pasted a clipart image. I am using the butterfly below:

Open the image in Photoshop or Photoshop Elements. If it is vector clip art, you will need to convert it to TIFF, PNG, or BMP first. Avoid converting to JPEG because it will distort the crisp lines in the image. To achieve this, click on File > Save As, and then select one of the formats listed above.

Make sure the image is in RGB color mode (Image > Mode > RGB color).

Go to the layers palette and click the second button (adjustment layer), then choose Threshold.

When the Threshold dialog comes up, your image will be converted to line art. If you move the slider to the left you will get less black, and if you slide it to the right you get more black. When you like the results, click OK.

Next we need to merge all the layers. Select Image > Flatten Image:
Now if you are going to use this as a coloring sheet we will need to print the results. Click File > Print:
This opens the Print Preview dialog box. Notice how small the butterfly appears.

To make it larger, simply grab one of the size handle boxes and pull it out while holding down the left mouse button.

Click OK to print your photo.
You can also color it is Elements by using the magic wand tool
and clicking inside an area. To select more than one area, simply hold down the Shift key. Then select Edit > Fill Selection and choose either a pattern or solid color. To select another area you must deselect the region. To deselect select Ctrl + D. Here is what I came out with.