529 college savings plans have attracted $100 billion in 11 million accounts, roughly a quarter of the money parents in the U.S. have set aside for their child’s education. But that’s far short of the hundreds of billions of dollars asset management firms expected them to attract.

And after many of these funds underperformed in the already difficult market of 2008, many 529 administrators have been lowering fees and increasing the conservative options in their plan to make them more appealing.

But because each state that sponsors a 529 has different tax exclusions and rules, and in many cases, offers multiple 529 plans, they are extremely confusing to investors, The Wall Street Journal reports. In fact, according to Savingforcollege.com, there are more than 3,000 investment options available in 529 plans.

In addition, the plans report fees in widely different formats, making comparisons frustrating, and approximately 18 states don’t offer tax breaks.