I mad my own template by using a template with a 16 squares and duplicating 8 spots. The template had squares for photos, but in the end I made them rectangular and I tilted all the photospots I had.
This is how it turned out, pretty simple in the end with just a few wordart pieces and 2 little clusters:
Or you might want to check the Weekly templates by Erica Zane, maybe there is one with 24 photos, or you can create your own out of these templates.
And finally, you might want to check out the Stitched Grids by Traci Reed. Here is 1 of her packs with a template with at least 24 photospots.