Comment by semi-extrinsic

Can recommend having an oldschool landline phone.

When my oldest was 6 and started walking home from school by herself, we got a cheap push-button landline phone and an cheap no-name box where you would plug power and a SIM card into one end and the phone cord into the other end.

Taped a piece of paper with our phone numbers to the phone mount, and she would call us almost every day when she got home just because she could. And she still remembers our phone numbers by heart, 7 years later.