THE Maryland General Assembly this year approved two important bills concerning children. One is aimed at getting more children adopted who now live in foster homes. The other attempts to ensure that children in the custody of one parent can't be kidnapped with immunity by the other.

The average foster child is 12 years old, has lived with three different families during the eight years he's been a ward of the state and, because of his age, is likely to remain in a foster home until adulthood. These facts underscore a serious problem of foster care for the 13,000 foster children in Maryland and the 500,000 across the nation: For most, a nominally temporary placement has become a long-term condition. Often this occurs for lack of a systematic and vigorous effort either to return these children to their natural parents or to have them adopted.

The bill passed by the General Assembly is similar to that of several other states; It creates so-called review boards of citizen volunteers and state officials with the intention of speeding up the transfer of children from foster care to more permanent family arrangements. The boards' official powers are limited to reporting on whether public and private agencies are making the necessary efforts to get these children out of foster care. But that public scrutiny can be a valuable tool in improving the lot of foster children.

Although exact figures are lacking on the incidence of "child snatching," the practice has been occurring with greater frequency in recent years. Usually, it involves the losing parent in a child-custody decision kidnapping the child from the former spouse and taking him or her to another state. The difficulty has been that few states considered this peculiar kind of kidnapping a crime. Thus, the parent who was the child's lawful guardian had to file a civil suit - a cumbersome, time-consuming process - to get the child back. Sometimes, the awful result has been parents' repeatedly "stealing" their children from each other. By making the act a misdemeanor - thus authorizing police intervention - the General Assembly has made it possible for the child to be returned to the guardian quickly and a solution to be reached speedily in criminal court.

The General Assembly also passed legislation that extends the state's protection to children physically suffering from parental neglect and creates an office to coordinate all state programs involving children. These four bills should improve considerably the state's ability to aid children who, in a variety of ways, are dependent upon it for protection.