children served. (4) The results of the most recent self-assessment under section 641. (5) Information about parent involvement activities. (6) Information about the grant recipient's efforts to prepare children for kindergarten. 643. Records Each recipient of financial assistance under this subchapter shall keep records, including records which fully disclose the amount and disposition by such recipient of the proceeds of such financial assistance, the total cost of the program or activity in connection with which such financial assistance is given or used, and the amount of that portion of the cost of the program or activity supplied by other sources. 644. Research (a) Study The Comptroller General of the United States shall conduct a study— (1) of the different approaches and best practices used by States and Indian tribes in carrying out the program under this subchapter