I do have one (probably stupid) question. How does one register here? I've noticed that on the CTK exchange some of the contributors are guests while others appear to be members. I have not been able to find the link for membership registration.

Thanks,
Owen

Thank you for the kind words.

> I hope to use it in several of the
>classes I teach.

If you do, I'll be extremely curious to learn of your impressions: what worked with the students and what did not.

>I do have one (probably stupid) question. How does one
>register here? I've noticed that on the CTK exchange some
>of the contributors are guests while others appear to be
>members. I have not been able to find the link for
>membership registration.

There are two unrelated registrations. You can register at the CTK Exchange which allows you to be notified of new posts to the topics and, if I am not wrong, to the forums of your choice.

The registration at the site proper has a sole purpose of supporting this site. There is not real benefit there, except that some dynamic advertisement is excluded for the registered users, but there is not much of it anyway. This registration is temporary and is available via the shopping cart icon at the top red/yellow navigation bar.