This experimental study aimed to determine: 1) Differences in science learning outcomes between students who were taught via the Science Technology Society and the Quantum Teaching models; 2) Differences in science learning outcomes among students who have high, medium, and low critical thinking skills; 3) Relationship between these learning models and the critical thinking skills in terms of science learning outcomes. The participants of the study comprised 300 students from fifth grade of the private primary school in the Surakarta region. Out of the 300, 150 studentswere in the experimental group and 150 were in the control group. For the data collection two-way analysis of variance followed by the Scheffe test were administered. The result of the study showed that 1.) The level of science learning outcomes of the students who were taught via the Quantum Teaching model were higher than those taught via the Science Technology Society model. 2) There were differences in the level of science learning outcomes among the students who have high, medium, and low critical thinking skills. 3) There was no relationship between the learning models and the ability to think critically for improving science learning outcomes.