The mailing lists seem to be functional. Invitations to subscribe have been sent to current Clicktrain and NPSO members. If you didn't get your invitation, go to the information page for your list to subscribe.
Publicly available lists
tardigrade.net is now using mailman for mailing lists. You can control your settings at a web page. To get to your settings page, go to the list information page for your list and follow the link at the top. You can also type in the link below, and replace 'listname' with the name of your list:
Official mailman list member documentation
Subscribers using yahoo.com, aol.com, or other email service that implements DMARK bouncing, will not have a good list experience. At the best, messages will likely be delayed by 4 hours or more. Because DMARK rejects so much valid mail, subscribers will also probably be automatically unsubscribed frequently without notice (because the notice would also be rejected).
You may have somewhat fewer problems if you switch to the digests, but there's no guarantee.
I strongly suggest that at least for list mail, you get an email account with a responsible service. The best choice I've found is fastmail.com, which is $30 per year, but in addition to well run and secure email, it has many useful extra features, such as fetching your mail from your other email accounts to have it all in one place, and web space for photo galleries or sharing files.
If you can't pay for email, a good free alternative for light use (less than 150 messages per day) is Proton Mail. It has a web interface (many of the features are only available for paid accounts), and there are also mobile apps.
There is one other possible workaround for lists that have archives. If you subscribe to the list then set your subscription options for "Mail delivery" to 'disable', you can read the messages in the web archive even if the archives are limited to subscribers, and still post to the list. Since no list mail will be sent to you, it won't bounce and cause you to be unsubscribed.
Send mail to the WebMonster: webmonster via tardigrade.net