diff --git a/block.go b/block.go
index f999f71..325baa0 100644
--- a/block.go
+++ b/block.go
@@ -570,7 +570,7 @@ func (b EquationBlock) MarshalJSON() ([]byte, error) {
 type ColumnListBlock struct {
 	baseBlock
 
-	Children []Block `json:"children,omitempty"`
+	Children []ColumnBlock `json:"children,omitempty"`
 }
 
 // MarshalJSON implements json.Marshaler.