The link below is for an excellent and clear document on sauerkraut that should make everything clear. Then if you have additional questions, just ask away.

Carol

Here is a link that might be useful: Make Your Own Sauerkraut

My recommendation: team up with someone who will help with the shredding and preparing the cabbage for kraut making. It will be fun and easier if you have a friend to share the fun and Kraut.

You can roughly figure a pound of food fits in a pint jar.
38 heads is a LOT of cabbage! Even if they're small and only weigh a couple of pounds each, you're talking about more than 75 lbs. The weight will shrink some as it ferments, but still going to be a bunch.

Are you planning to make it all into kraut?

Deanna