Oxygen Theme Description http://theme.wordpress.com/themes/oxygen Live demo site http://oxygendemo.wordpress.com/
In Oxygen you can either have a Home page that displays your posts or a static front page ie. a Showcase template.
Showcase page template
When you first activate Oxygen, you’ll see your posts in a traditional blog format but if you’d like to showcase your content in an online magazine-like fashion, then you can use the Showcase Page template. ...
The front page of the blog by default will display your posts (not pages) in reverse chronological order, with the most recently published post on top. IIf you choose a static front page in order to use the Showcase template for a post slider then you have to create two pages because you will need one for your posts to display on. Settings > Reading is where you make the designation change and click “save changes”. http://en.support.wordpress.com/pages/front-page/#setting-up-a-static-front-page
Post thumbnails are 470 pixels wide, unless you make the post Sticky to show off in the featured slider, in which case they’re 750 pixels wide. Keep in mind: if you mark a post as Sticky but the featured image is less than 750 pixels wide, then it won’t display in the slider and will still disappear from the river of posts.
Please be aware that you cannot crop the sticky post thumbnails.
Sticky post thumbnails are 750 pixels wide in the featured slider
Regular post thumbnails are 470 pixels wide
If you don't see the page attributes module then make sure that you don't have it hidden in your screen options http://en.support.wordpress.com/screen-options/
Modules to unhide:
Post – Likes and Shares, Format*, Categories, Tags, Excerpt, Send Trackbacks, Discussion, Comments**, Slug, Author, Revisions, Writing Helper
Page – Likes and Shares, Page Attributes, Featured Image, Discussion, Comments**, Page Revisions, Slug, Author, Revisions, Writing Helper