is it against TOS to use hidden text like student loan consolidation near the ads unit for higher CPC?? plz tell me. if not . then i want to use hidden text.
Many people came up with that idea before. Hide your text contents, I think that is called "cloaking", The contents search engines/bots see is not the same of what human readers see. You will get penalize for that as Google already said no "cloaking", don't risk you adsense account man.
There's a fine line between hiding content, and having your text color be something very similar to your background color. I'm pretty sure that the Google bots are searching for the same code for your BG and Text...so if you have #ffffff for both, it's going to raise a red flag. But if you had #ffffff for your background and #fefefe for your text, it shouldn't be a problem and it will blend almost perfectly. I'm not saying you should do this, but if just make sure you change the text color code a bit if you do.