Your child will already have some experience of full and empty. Extend their understanding by explaining half full, nearly full and nearly empty.
Provide opportunities to explore capacity using water, sand, rice, cereal, bolts, Lego etc.
Give your child different-sized containers and different shapes (narrow, wide, tall, thin, shallow). Ask your child to pour items (like rice, flour etc) from one container to another. They will also enjoy playing with scoops, ladles and spoons – can they count how many spoons it takes to fill each container?