When parents ask me what they can work on at home with their students, I think they usually have academics in mind. I teach my daughter reading and math at home, and I am happy for the parents of my students to take on ABCs and 123s at home as well. But when I hear "What should we be working on?" it's social and behavior skills that always come to mind. I suspect that's true for many teachers, whether they are teaching 3 year olds or 13 year olds. The more our students know how to get along with others, follow directions, and be a part of a group, the more teaching we teachers can do.
Accordingly, my top goals for 3 year olds are mostly social and behavioral. I would put "following directions" or "being a first-time listener" at the top of the list, but these goals are meant to be more granular and approachable. My goal is to help parents know where to set the bar. Three-year-olds were non-verbal toddlers just a minute ago. Their parents think about where they've come from and see so much growth that I think it's hard for them to remember to keep inching the bar up on what they expect their children to be able to do. In fact, I think remembering to move the bar and knowing where to set it is the predominate challenge of contemporary parenthood. With smaller families and more spread out extended families, we just aren't around kids that much until we become parents, and so we're always flying by the seat of our pants.
A final note on my goals is that they include two important hygiene goals, not putting hands and toys in your mouth and coving your coughs and sneezes. The pandemic has made me more painfully aware of the need to teach and enforce hygiene standards, but these goals have always been and will continue to be super important. Kids don't just get sick more because they have weaker immune systems; they get sick more because they encounter more germs. That's why children in childcare get sick more than children at home. And childhood illness should not be viewed positively with an eye towards building up their immune systems. There are so many viruses, like the flu and the common cold, that evolve too fast for natural immunity to fully protect us. That's why childcare workers get sick more than other professionals, even though they've had years to build their immune systems. They just encounter more germs. Teaching your child to keep their hands out of their mouth is like wearing a mask. It benefits everyone around them.