5 years is old enough for the junior/4+ sets. Those sets have larger parts and can be build within the attention span of a child. And they are mostly something

5 years is old enough for the junior/4+ sets. Those sets have larger parts and can be build within the attention span of a child. And they are mostly something hands on like cars or planes that the kids like to play with. Then even larger sets can be cool for children. I just bought and build the current moon station but that turned out to be not as good looking as I imagined. But my daughters (4 and 6) immediately took control of it. Especially the pizza dispenser was a highlight for them.