Previous measurements of the nuclear modification factor $R_{AA}$ at RHIC have shown a strong suppression of neutral meson yields in central Au+Au collisions for $p_T$ > 5 GeV/c independent of $p_T$. Over the first five years of operation the PHENIX experiment at RHIC has collected a wealth of data for various systems and collision energies that is providing valuable information for the understanding of the suppression pattern observed in central Au+Au. Recently Cu+Cu collisions at various energies ($\sqrt{s_NN}$ = 22.4, 62.4, 200 GeV) were added to the previously measured set of collision systems (p+p, d+Au, Au+Au). With this extended data set we now have the possibility to compare the influence of various production mechanisms on particle production in much more detail. We will present $p_T$ spectra of $\pi0$ and $\eta$ mesons for different collision energies and systems and compare to theoretical models.