In researching grammar for various levels of young learners, I discovered an interesting resource I’d been previously unaware of. These are websites which list all of the grammar points for each level of young learner.
Generally speaking, this style of website details the rules of each grammar point, and provides examples of its use (along with common errors). Some websites also provide free exercises you can complete in order to test your (or your student’s) knowledge.
Test English is the website I’ve been using to explore the typical grammar points for Starter level children, and I’ve found it to be very useful. There are others, though. If you teach young learners, I’d encourage you to take some time to explore them.