The benefits of breakfast consumption for the health and well-being of children, adolescents, and adults have long been documented. These benefits extend to the academic domain where breakfast consumption has been associated with stronger academic motivation and achievement, which is why some developing countries incorporate feeding programs for students from lower SES families. More recently, dinner has been referred to in relation to achievement, but more specifically in relation to having family dinners together as an indicator of strong family support for learning. The Philippine data (n = 6108) from the PISA 2022 were analysed to test the hypotheses that (a) breakfast and dinner consumption relate to mathematics performance, (b) these relationships are mediated by stronger perseverance and curiosity, and (c) these relationships are moderated by the students' SES. The PROCESS module in JASP (v. 0.19.3) was used to the the moderated mediation model, and the results show: (1) significant total and indirect effects of both breakfast and dinner consumption on mathematics performance, but stronger effects associated with dinner consumption, (2) curiosity and perseverance mediated the preceding effects, (3) SES enhanced the indirect effect of breakfast and dinner consumption through increased curiosity, but not through perseverance, (4) the direct relationship between dinner consumption and mathematics performance was stronger in higher SES students, but the direct relationship between breakfast consumption and mathematics performance was only found in lower SES students. The results generally support theories on the motivational benefits of breakfast, and these benefits are most notable among lower SES students. The motivational benefits of dinner are stronger among higher SES students, which suggests that other resource-related factors may be associated on the benefits of dinner. Implications for nutrition-related programs for economically vulnerable students are discussed.