They're learning the same paradigms as their older siblings, but at a bit of a slower pace.
They've begun learning the parts of the body and left and right. We play Simon dites … or sing Alouette, pointing to various body parts. They've also begun learning the verbs lever (lift up), baisser (put down), toucher (touch), and montrer (show). Sometimes I'll ask them, 'Où est la main gauche?' and they answer, 'Voilà la main gauche!' while pointing to it or holding it up.
They're learning how to count to ten. I'll hold up fingers and they have to tell me as quickly as they can how many I'm holding up. I pulled out the old pre-school number flashcards and they use those for practice, too. I've heard them counting things in French - plates when setting the table, or cups of flour for a batch of pancakes.
Les Couleurs. I simply point to something or hold something up and ask , 'Quelle couleur est-il?' and they answer by saying, 'Il est …', naming as many colors as they can.
Yesterday, we also started working on the names of rooms in the house and parts of a room (floor, door, ceiling, window, etc.). They're most recent paradigm is aller, so we'll be able soon to talk about going into different rooms in the house or touching the wall or the floor.
I have a list of topical vocabulary I want to teach them, along with verbs and some aural constructions (il est … vs. ils sont …, la main droite vs. le pied droit, etc.). We'll simply move through them as we can. I'm also astounded at how much they're learning and how much they all seem to be enjoying it.
An added benefit is that I'm reviewing my French and am filling in some of those holes that have cropped up through my years of not using it.