Follow the leader. No marching required! Just have your child imitate upper-body movements, like clapping hands or waving arms. When she gets the hang of it, have her mimic a series of claps, waves, knee slaps, shoulder shrugs, and head nods.
Scavenger hunt. Draw pictures of household objects, like a cup, a hairbrush, and a pillow, then time your kid as she searches for the real things.
Sound off. Do your best impression of an animal ("Woof!") and ask your toddler to guess what you are. Once she gets it right, let her copy your sound, then move on to another animal.
Ball game. Sit on opposite ends of the sofa, then roll a ball between you, naming a new color each time one of you gets the ball. Let your kid chase after it if it falls.
Stick together. Draw a shape on a sticky note and have your child attach it to something that has that shape, like a plate for a circle or a book for a rectangle.
Sock it to me. Hold open an empty laundry bag while your child tries to score baskets using rolled-up socks. Gradually change the size of the bag's opening from large to small to keep the game interesting.
Don't wake the giant. Pretend to sleep while letting your toddler try to steal your blanket without "waking" you. Shift around and snore to build suspense, then roll over with a roar and tickle her silly. The only challenge? Not actually falling asleep.