Be patient, you will find your groove.

They are rabbeted in the very best tradition of foursquare work, and each of the 4 and 5-inch quartersawn trim boards has a wide single groove dadoed into its back (modern production trim boards have 2 or 3 narrow grooves, it's cheaper to do but doesn't work for trim quite as well).

Some laminates also make stair-nose edging that nails/glues to the stair edge and allows the rest of the floor plank to float, secured in a groove in the edging. 

i was going to cover it with vinyl soffit, but i saw some other houses near me that had a stained tongue and groove  porch ceiling . 

Sometimes you just gotta find your groove!

Do you like the tongue and groove floating type or the glue down?

If they are three tab shingles look at how  far apart the grooves are.

Either way they they are grooved on all 4 sides.

This would run in a dado (groove) along the length of the box. 

The make your own tongue-n-groove type, so when they start eating lunch with you , it means something.