This implies that multiple parties (e.g., the other grandparents and the parents) can contribute to the same Plan so long as the total contributions don't exceed that limit. Is this an accurate surmise?

My mother, grandmother, and sister have all written contribution checks to my kids' 529 accounts for Christmas and their birthdays. They've all cleared and added to the accounts, but I don't take the income tax deduction on my state income tax for the contributions they make.

This implies that the tax due on excess distributions is to be paid by the beneficiary, correct? If there is money left in the Plan after the kid has graduated, can he use the money for graduate school?

This IRS document makes it appear that the answer to the first question is "yes": http://www.irs.gov/publications/p970/ch08.html#en_US_2010_pu...

This page says that the answer to the second question is also "yes", so long as the plan itself allows it: http://www.finaid.org/savings/529plans.phtml

Who "owns" the Plan? Do I as its creator? The parents? The beneficiary?

When I opened accounts for my kids in Ohio, there was a question on the form that asked for the account owner's name & address, & the owner needs to sign the form. I put my own name, and I'm getting all the mail and paperwork from the plan. The form says the owner needs to be 18 or older. Here's a link to the Ohio form: http://www.collegeadvantage.com/userfiles/media/30_New%20App... . If the account owner is someone other than the parents, it probably makes sense to communicate with the parents to avoid surprises...

How does one determine the total education expenses? Is it really as simple as looking at the school's tuition and book costs and guesstimating that value into the future, with the actual total costs to be determined in real time?

This IRS page shows what counts as "Qualified Education Expenses" and how they're documented: http://www.irs.gov/publications/p970/ch08.html#en_US_2010_pu...

Losses on the account: these are claimable by the investor (under certain circumstances). Allocating such a loss across multiple investors can get complicated, which implies it might be better for the multiple potential contributors to set up their own Plans instead. My question here is whether, in order have such a loss, would all the Plans for the same beneficiary need to be aggregated (in a way loosely analogous to multiple Trad IRAs for a single RMD) and a net loss realized before a loss could be claimed, or are the several Plans treated individually for this?

That one, I'm afraid, is above my Google-Fu (http://en.wiktionary.org/wiki/Google-fu) skill level this morning. That said, over the 17 to 18 or so years between our kids' births and their potential entries into college, across all the "dollar-cost-averaging" style contributions we're making, if our kids' 529 plans create net taxable losses, we've likely got bigger problems than how to deduct any such losses. Our personal perspective is that the 529 plan is a "protected" account to sock aside money to pay for college, with a little bit of potential tax benefit along the way. Should our kids not need the money for college at all, we'll cross that bridge when we get there.

-Chuck
Inside Value Home Fool