STEM-Based local and National Clubs
Note that many Boys & Girls Clubs, YMCAs, etc. also run STEM programs.
Springfield STARS
Springfield telescope & reflector society. Lots of astronomical fun.
Mass Audubon
They have a lot of nature & wildlife programs for members & non-members.
Allen Bird Club
Springfield-based birdwatching club.
https://www.allenbirdclub.org/
Anti-racist Collective of Avid Birders (ACAB)
Based in Western MA, not just for BIPOC, they focus on making birdwatching accessible for those with disabilities, etc.
https://www.facebook.com/groups/acab413local/
Athol Bird & Nature Club
Bird watching club.
Hampshire Bird Club
Bird watching club based in Hadley.
https://hampshirebirdclub.org/
Northfield Bird Club
Bird watching club.
https://www.northfieldbirdclub.org/home
Connecticut Valley Mineral Club
Mineral club, based in Springfield.
https://www.cvmineralclub.org/
Girls Who Code
Westfield Technical Academy – local branch
4H
Organization based on agriculture, etc.
Pioneer Valley Women in STEM
Regional network of women in STEM
Hampshire County RC Club
Model aviation club
http://www.hampshirecountyrc.org/
Hampden County Radio Association
Radio club – building & using
Springfield Garden Club
Garden club
https://www.springfieldgardenclubma.org/
Science Explorers
Online & in-person after school STEM clubs
https://scienceexplorers.com/our-programs/after-school-stem-clubs/
Big list of STEM clubs & camps in the US
Some of these are nation-wide, while others are more local. Some offer summer programs.
https://stephanieschuttler.com/big-list-of-stem-clubs-and-camps-in-the-united-states/