I'm not sure why a kid needs a smartphone. Most kids are around safe adults (teachers at school, parents at home, teachers/coaches at sports/other activities) and can always ask the adult to look up something online or call parents if needed. Why do they need a phone? Even kids that travel alone (maybe a teen that takes a public train or bus) at best needs a dumb phone. Why do they need a smartphone? And tablets are even worse.
To add, almost all kids I know have laptops or Chromebooks for school work. So I'm not sure why a smartphone is needed. I'm genuinely curious
My boys are 11 and 13. The 13 year old got an old smart phone when he started 6th grade and had a 25 minute walk to school. Unfortunately, there are no payphones any more so a phone is a must these days, sigh. I had thought about a dumb phone, but all the dumb phones my plan was offering were designed for old people with giant buttons and no texting. I bought a very old smart phone, mostly b/c I thought we would text. His phone has to be turned off for school, so I hoped I could shoot him a text during the day, he would turn on phone right after school and see it. Things like "Cross country was cancelled tonight, just come home". What really happened is that he keeps his phone off 99% of the time and then turns it on when he wants to call someone.
The older boy lost his phone, so I got him an old model smartphone (still hoping to get him to text). Then we found it two weeks later and I gave the original phone to my 11 year old who just started walking to a new school building 20 minutes away. He also won't text.
My 13 year old has cancer, and we did buy him a tablet for all the times he sits in chemo, the hospital and the like. We will not buy one for our other son and would not have bought one for the 13 year old if he had not gotten sick. He does get a Chromebook for school work, but has to turn it into the school in the summer, so no personal computing device in the summer.
I have consumer cellular and pay about $45/month for service for their phones and mine. We share a pool of data.