This is really going to depend on where you live, your skin type, and prior sun damage.
I had a number of blistering sunburns before puberty (my first one was recorded in my baby book... father stationed in Hawaii). By middle school and high school, I'd get sunburned in gym class if we were outdoors. If I'm out in the sun without sunscreen, I get a rash on my arms.
My dermatologist says the benefits of sunscreen outweigh any risks for me. I've had a number of dysplastic moles removed and go in to be looked over every 6 months.
I try to put sunscreen on my son if he's out during the summer from 10-4. He has my husband's skin and does seem to tan rather than burn.
And as an FYI for everyone... get to know the ABCDs of mole changes and do a self check regularly. Watch for moles especially on palms and soles of feet. A friend lost his wife due to a melanoma from a mole on the sole of her foot. (I'm doing a family medical history today so cancer is on my mind... and Alzheimers and heart disease... what fun :glare:)