Ask any dermatologist about the most under-used piece of sun protection and you'll hear the same answer: the hat. Not the cap. The broad-brim hat.

Here's why it matters. A cap shades the face, but leaves the ears, the neck and the sides of the face exposed, and those are some of the spots that catch the most sun over a childhood. A broad brim shades all of it, all day, with no reapplying and nothing to rub into stinging eyes.

The catch, of course, is getting kids to keep one on. The trick isn't nagging. It's making the hat something they want to wear. Let them choose it. Make it part of the going-outside routine, the same way shoes are, so it stops being a negotiation. And pick a hat that's actually fun. (Ours fold up into a sea creature, which turns out to be a very effective bribe.)

A few things that help:

• Start young. A hat that's always been part of the routine rarely becomes a fight.
• Let them own it. Their choice, their hat.
• Keep a spare in the car and the bag. The best hat is the one you have with you.
• Lead by example. Kids copy what they see.

A broad-brim hat is one of the easiest wins in sun safety. It never needs reapplying, it protects the bits sunscreen always misses, and once it's a habit, it just happens.