Is there a way to get all the power-ups in the red mushroom houses in New Super Mario Bros. Wii?

Each world has 6 possible panel combinations. There is a guide on GameFAQs detailing the different panel combinations, and which ones you should hit to test what the current arrangement is.

Also, here's a visual guide to the panels.

Each level has 6 different layouts. Once I had those in text form I wrote a small program that generated a PDF based on these. The items with green background do not have any Bowser (Jr) in that world in that position and can be safely clicked (if you know the green patterns, you always get at least 3 items from the red mushroom).