Simple text plugin

Hi,

I’m new to wordpress. I’ve built a website for a friend and i’ve hard coded some HTML text into the index page, there is 3 blocks of text. Is there a plug-in whereby I’m able to add a php tag here and give my friend the ability to change this text from within the admin area.

By the way, this can’t be used by a post or page excerpt or any other standard functions as they are being used for something else. I thought this would be a simple thing but i have looked for the plug-in and aren’t able to find something that resembles what i’m looking for.

Any help is appreciated