Avoid locking your keys in the car
I'm terrified I'm going to lock my son and my keys in the car together. So, when I'm putting my son in the car or getting him out, I put my keys on the roof of the car. I can put everything else in the car along with him (my purse or any shopping bags), but the entire time I keep the keys on the roof.
Of course, I drive a car, so the roof is pretty easy to get to. My sister-in-law drives an SUV, so she puts her keys on the hood.
I, too, am afraid of locking my keys in the car with the kids. I've attached a carabiner to my keychain so I can hang my keys on my purse strap when I need hands free. Another benefit: I keep them clipped to my purse when not in use, so can see at a glance if I've got my keys with me when grabbing my purse to head out the door.
How do you keep from locking your keys in the car?
Related: Keychain hacks