Blue Sky in Adobe Photoshop

0 - Better Blue Sky (Photoshop Tutorial). I'm learning how to use Photoshop Elements now that I've got my 35mm scanner working. Wow, its a hard product to learn. Very powerful, but very difficult.
Current thing I'm learning is how to make the sky more blue. I wish I had used a polarizing filter on my camera to make the sky better. Here's a quick trick I found on the web in lieu of this.
"Digital Film Tools": has an Adobe Plug-in that emulates a circular polarizer which is what I need to make things really look darekr.
Next step is learning how to lighten an area that is underexposed.