The purposes of this study were: 1) to determine the efficiency of a Thai language entence making skills package for Prathomsuka 2 students; and 2) to compare the achievement f these students before and after using the skills package. The sample of 18 Prathomsuksa 2 students from Ban Chokdee School in Borwen Sub-District, Klung Distriuct, Chanthaburi Province, in the first semester of academic year 2017, was selected by purposive sampling. The research tools used were: 1) the sentence making skills package; 2) the sentence making lesson plans; and 3) the sentence making skills achievement test. The data were analyzed by using: percentage, mean, standard deviation, and t-test (Dependent Sample).