Finding the sweet spot between teaching a more complex version of history and focusing on great men, dates, and places with students can be a tough line to walk - especially when it comes to slavery. The good news is there are lots of organizations that sit with questions like the ones you're asking and work to find solutions.

Teaching Tolerance, out of the Southern Poverty Law Center has the most comprehensive set of resources that I'm aware of. The podcast series on "Teaching Hard History" is excellent and works through various scenarios, topics, and talks with teachers around their questions and what's gone well. One of the most important episode is when they talk frankly about gamification and re-enactments and do a great job laying out how if a teacher does feel the need to ask students to do first person "in the shoes" type tasks, it should move students towards empathy for enslaved people (not the enslaver) and should avoid asking children to "act" as slaves. This piece talks about teaching Kindergartners about slavery, and explicitly attending to the enslavement of Indigenous people.

TT also regularly reviews picture and YA books that teachers can use to teach the topic - which is how I learned about Never Caught: The Story of Ona Judge. Teachers, and their students, that I know who have read it sing its praises. It's a hard read but accessible. That is, she explains what it means to be enslaved in terms of a loss of control and choice over how she spends her day and that at any moment, her owner could send her away.

If you're familiar with the 1619 Project, the Pulitzer Center put together an entire curriculum on the project, complete with a lesson builder for teachers. The piece I most appreciate about the project is the reading guide invites the teacher or adult who plans on using the curriculum to spend some time reflecting on their own thinking and understanding about the chattel slavery system in the United States. Given most teachers are white women, the work before the teaching is critical. (I get into that a bit more here.) Students are more likely to think there's something wrong or untoward about talking about the topic if the teacher is skittish.

Finally, Teaching for Change has some useful, explicit resources on the topic. What you'll likely notice is that a lot of the work is very similar to how parents are advised to talk to children about sex - spend some time figuring out your own issues, start slow, and follow where they lead.