How do I take an older iPad and give it my husband but leave data on it intact. He has his own Apple ID for his Mac.

You cannot really. If you leave your iCloud data on it and he signs into iCloud with his AppleID, all your data will merge with his, messing up his account.

You should really wipe it so he can set it up clean with his AppleID and data -> What to do before you sell, give away, or trade in your iPhone, iPad, or iPod touch - Apple Support

Just be sure to make a fresh backup while it has your AppleID before clearing it for his use.

To answer your question.

When changing to the new ID, there may be some data loss, but you can minimize it. If syncing photos with iCloud, ensure Optimization is turned off in Settings/Your Name/iCloud/Photos and/or in Photos/Preferences/iCloud. Then make sure full resolution photos are on the device/computer. When signing out of iCloud, if asked whether you want to retain data, choose yes. Messages conversations will be lost if they are addressed to the ID. See the article below for other places that the old ID should be removed. See Winston Churchill's response in the below discussion. If possible, also set up Family Sharing  between the IDs to keep access to your apps/purchases. 

 How to switch Apple IDs on your iPhone or iPad.      

How to transfer all files from one iCloud account to another.       

What to do after you change your Apple ID or password - Apple Support.      

Family Sharing.         

Family Sharing - Set up.        

As has already been pointed out, it would be far, far better to set up your old iPad fresh completely for your spouse to start using.

However, one thing you can do though is use his Mac and open up with website https://www.icloud.com and log in there with your own (not his) Apple ID onto that web page. This will allow you to see a good portion of your iCloud data, like if you have files and pictures iCloud. He can copy a lot of that data onto his Mac from the iCloud website then could sign out of your Apple ID on the iCloud page, and bring up the iCloud page using his own Apple ID and then upload that to the iCloud webpage to have a copy on his own account. Again, this is all using the Mac.

Then that data would be available on the iPad if he turns on the specific iCloud features to sync with.