Often, I ask our younger students what they did at school today.
I might ask how many lessons they had, what time they arrived at school in the morning and left in the afternoon.
Also, what they had for lunch and whether it was tasty.
We can probe a little deeper each week, gradually introducing new grammar and language in such a way that students become familiar with it through use, not textbook study.
For example, asking which lessons they enjoyed most and least, which was the easiest and which was the hardest. Also, whether they have a lot of homework or a little can easily be conveyed with gestures. How many children don't want to tell you the size of something?