And remember, with six kids around you wanting to “help” you may need to measure three times before cutting once!
At Home Depot, if you bring in measurements, you can cut your the wood you purchase for a tiny fee (like 25¢ per cut) on their saws. And if you find a helpful soul, they might even cut it for free, or at least do the cutting for you (bring in your baby so that they will see that you need help). Use at least 1/2" plywood for the shelves so they don’t sag. Don’t forget to support those shelves, perhaps with a strip of 1/2" quarter round underneath each shelf. And you can finish the front edge by gluing on some trim to round the rough edge of the plywood. I think that pretty much says everything I know about construction. You can even buy nice looking trim, so that if you want to paint the pantry, it will look good. Also, if you are going to put a door on the pantry, check the damaged-goods section of the store. Maybe there is something there already that you can use. Those prices are definitely negotiable.
I’m so proud of your husband. I knew he could do it! And you did it to. God bless your precious family.