Relating to a limitation on the total amount of ad valorem taxes that a school district may impose on certain residence homesteads following a substantial school tax increase.

The bill text for HB 642 is unavailable in the provided context, and no specific provisions or policy changes are described. The title indicates it relates to limiting ad valorem taxes on certain homesteads after a school tax increase, but the actual mechanisms or affected parties cannot be confirmed without the full bill text. Since the content is not accessible here, a factual summary of the bill's provisions cannot be generated. For accurate details, the full bill text or official summary should be consulted.