It's a decent, turn-off-your-brain entertainment for young adults and their families. The only thing that keeps it from being a good-for-all-ages show is its propensity for sexual innuendo. It's unnecessary to have it in the show, but almost every episode has some allusion or other to sex. Some may call me a prude, but I don't think that children NEED to have sex thrown in their face every time they turn on the television; especially when it is between unmarried people.
On the UP side, the show does discuss a variety of REAL scientific theories, discoveries, and concepts.
Don't expect that you'll get SMARTER by watching Eureka, but at least you won't regret wasting an hour of your life watching it.