Using "hide" and "show" for sprites, and switching backgrounds for the stage

Dear Colleagues,

I really enjoyed the creative adrenaline and warm feeling of camaraderie from the Scratch @ MIT conference from Aug. 11-14. 

I'm switching from several year of working with MicroWorlds and its Logo language-syntax-based programming to Scratch this fall.

I'm trying to create a "skateboarding / snowboarding" animation, and I want to hide or show one sprite and one background, for either type of recreation.  But in Scratch, the button sprite won't show a "change background" and I'm having trouble with designating the "hide" or "show" commands to a specific sprite.  In MicroWorlds, for example, I could write a program for a button such as:

to go_to_snowboarding
   page2
   show "skateboarding button"
   hide "snowboarding button"
end

Then I would create a parallel but reversed procedure and button, to toggle back and forth between the two pages.

I'm sure this is easy to do, but I've been unable to figure it out on my own.

Thanks for any advice you all might offer.

John Kendall
Rutgers Prep, NJ