The research purposes were (1) to develop the leaming package on the history
of Sukhothai Kingdom using cooperative learning management with LT (Leaming
Together) technique to be efficiency according to the 80/80 criteria; (2) to study the
effectiveness index of learning package; (3) to the compare acadernic achievement
results before and after learning; and (4) to study the study of students' satisfaction on
the cooperative learning management with LT (Learning Together) technique by the
learning package on the history of Sukhothai Kingdom for Grade 6 students. The sample
group was the 21 Grade 6 students of Ban Sawaiso School, Surin Primary Educational
Service Area Office 3 selected by simple random sampling. The research instruments
were (1) the learning package on the history of Sukhothai Kingdorn; (2) the academic
achievement test with difficulty index 0.71, discrimination power 0.49, and reliabity
0.88; and (4) the satisfaction questionnaire with reliability 0.96. The data analysis
statistics were the percentage, mean, standard deviation, and t-test (Dependent
samples).

The research findings were: (1) the learning package on the history of
Sukhothai Kingdom had the efficiency 92.77/91.30 and effectiveness index 0.84; (2) the
students who studied with the learning package on the history of Sukhothai Kingdom
using cooperative learning management with LT (Learning Together) technique had
higher academic achievement after learning than before learning at statical
significance level .05; and (3) the students had the satisfaction on the learning package
on the history of Sukhothai Kingdom using cooperative leaming management with LT
(Learning Together) technique was at the highest level.