Minimize toys that can be "figured out." Toys that facilitate exploration, building: blocks, art supplies, dress up. There are a ton of things out on the market now that kids can build things with - mine for some reason loved Magnatiles, but also Kappa blocks and unit blocks (the big, heavy wooden ones). Tinker Toys or legos (not the kits to build something) when she can be trusted not to put them in her mouth. Animal figures or dolls, so she can pretend play and make up scenes and stories. It's not as helpful for in the house, but just getting her outside where she can play with sticks, rocks, water.