I believe that young children need to learn the basics in this life first and foremost. They need to learn how to listen and obey. They need to be able to sit politely while eating, not throw their food, wipe themselves after eating, washing hands, saying please and thank you, playing nicely, sharing toys, etc. All of these things can be taught in the course of playing and going places.
Beyond that we do color, play with playdough, and I get them to help me use wetones to wash door knobs, wipe down their child sized table and chairs, and they help take care of the daycare pets. They love to wash their toys in water and bubbles too. Sometimes we come up with something creative like putting food coloring into shaving cream and playing with it while mixing colors. I haven't done that in ages. We sometimes paint with water colors or tempera paints. The art projects isn't really my favorite thing.
We also read and we tell stories. I encourage children to do as much creative play as possible. We like to look at videos that explain how things are done. There are some great sites online that help with learning. We go to time4 learning, starfall, abcmouse.com, and we are always trying other sites and looking for new sites to add to our list.
These are just some ideas and I prefer to come up with most ideas either on my own or to modify things I hear others talk about. So I do belong to lists online where I talk with other daycare providers.
The children of the ages you are talking about mostly need a clean, comfortable, visually appealing, and SAFE environment for exploration. Talking to them in a real way and not encouraging pointing and grunting is good too. There's no need to baby talk to toddlers. Playing games with them, laughing, and just cuddling is important at this age.