Here’s an idea for smell:
Get a bunch of small containers (I like to use film canisters; you can ask at the film counter for free). Poke small holes in the lids. For liquid scents, take a bunch of cotton balls and put different scents on them: vanilla, perfume, vinegar, etc. Place in the film canister and put the lid on. For solid scents, you can just dump the stuff inside. Your spice cabinet is a great place to look: cinnamon, peanut butter, cumin, chili powder, etc. Your kids can now smell and guess the scents.