There might be a https://brigade.codeforamerica.org/brigades/ section in your area. Some of the work is porting existing open source apps and make them work for your city. Last city (outside USA) I lived in there was a similar group with regular meetings, they even ran kubernetes cluster of services, making government data open (e.g. parsing PDF files and putting them into a database) and such.

I teach for a local non profit that offers computer science summer programs for high school students. It’s merit based admissions so there’s all kinds of different skill levels. It can be really hard to fill teaching roles for basic programming

That sounds awesome! What's the name of the nonprofit?

It’s called Nextech. They work out of Indianapolis so if you don’t live close there isn’t much of a chance to volunteer, but I think the idea of what they do is pretty common

I made a website that lists the parks / playgrounds in my city.

It was annoying to not know which parks had the features my kids could use such as toddler swings.

Am also working (slowly) on a way to easily browse what the city council votes on and how each member votes.

It is annoying that there is no way to know what my council member actually voted on when local elections happen without reading dozens of scanned PDFs.

I've participated in a few Give Camps (https://givecamp.org). They meet on a weekend, bringing charities and developers together so the charities can have a new starter web site, app, or upgrades to an existing site.

OpenAustin - making democracy work better through code, apps, and data.

I help seniors with their technology issues at my local senior center.