There are a lot of parenting tips out there, and it can be tough to know what to follow and what to ignore. So it's really nice when advice on raising children comes backed up with scientific studies proving that it works. 

Bryan Roche, Ph.D., a behavioral psychologist, has some particularly good, scientifically based advice to share. In a popular blog post at the Psychology Today website, he lays out some tips to help everyone of any age improve brain function. Along the way, he references studies that point up how three simple changes can raise children's IQ and improve their academic performance. These are all small changes that don't cost much and they're easy for every parent to do. You may even be doing some of them already:

1. Feed them Omega 3 fatty acids. 

We think of fish oil and other sources of Omega 3 as something older adults should take to ward off cardiovascular disease. But Omega 3 actually improves brain function in children, and the earlier they start consuming it, the better. It's present in breast milk, and mothers who breastfeed babies beyond their first few weeks of life provide Omega 3 to their babies, Roche writes.

Omega 3 is not found in most infant formula. That's unfortunate, because a randomized and controlled study showed that infants fed formula enhanced with Omega 3 had higher IQs than those who were fed regular formula even at the age of 4. It seems possible that the improved brain function Omega 3 supports when we're infants could be a benefit that lasts all our lives.

Beyond infancy, Roche recommends having children start eating fish as early as possible, and also broccoli and spinach. The drawback is that all three foods could lead to a battle if you try to get some children to eat them. Fortunately, walnuts, blackberries, raspberries, and strawberries are all excellent sources of Omega 3, as are blueberries to a lesser extent. You can also buy milk that's been fortified with Omega 3--it tastes the same as ordinary milk. Roche also recommends plenty of protein because it contains amino acids that support brain function.

2. Talk to them and read to them.

"The more conversations you have with your child, the more intelligent they will be," Roche writes. Playing simple teaching games along the way, for instance asking them to name or count objects, boosts their intelligence even more.

"You can raise your child's IQ by six points by simply doing this over a few years when they are young," Roche writes. Start as early as you can, he adds. The evidence suggests that, while still beneficial, you won't get as big a benefit if you start after your child is four.

Reading to children is highly beneficial too. "Kids whose parents read to them most days have higher IQs," Roche writes. This is especially true if you make reading an interactive process, rather than one where the child simply listens. Use different voices and emotions as you read and see which your child particularly engages with. Ask questions to make sure your child understands the story, such as "What do you think he's thinking?" or "What do you think will happen next?"

3. Expect them to be smart. 

This is such a simple tactic, and many parents may not know what a big difference it can make. In a groundbreaking study called "Believing You Can Get Smarter Makes You Smarter," psychologists taught students that intelligence is not a fixed quality, but is changeable and can be increased. Which is true, by the way.

They found that students who got this message both performed better academically and took academics more seriously than those who didn't. For parents, this finding points to a clear course of action. Tell your children they are smart, expect them to be smart, and make sure they know that they can be smarter tomorrow than they are today, and smarter still the day after that. Convince them that this is true. Because, if you do, it will be.