Take a look at the AD5220 data sheet. Figure 1 is a “Typical Push-Button Control Application”.
If you want at least 100, you can buy them directly from AD for $1.54, which is significantly less than DigiKey et. al. Don’t know if they would sell smaller quantities, but they might, especially for an educator.
You can also see https://makezine.com/projects/make-43/d … tiometers/ other for ideas.