To support the development of more robust conceptual knowledge, it is crucial to understand the alternative conceptions that students bring to the classroom, and how these can be considered and dealt with through instruction. In this study, we report the alternative conceptions of 498 students enrolled in secondary education in Ireland. A quasi-experimental design elicited student ideas about gravity, seasons, and the Big Bang. Our results show 15 alternative ideas held by students across all years, which are analysed with resource framework theory to identify conceptual resources used to explain each topic. Identification of these conceptual resources provided rich information about modes of hybrid understanding where students blended formal physics concepts with daily experiences. These results could support teachers in finding new instructional approaches to address preconceived knowledge held by students, given that even senior students held the same alternative ideas as first years.