My kids are too young to have this discussion yet, but I had no acceleration opportunities before high school. So I took Geometry and Algebra 2 the same year. If I remember correctly, it was totally fine to do them together and it would have been fine to do them in either order as well. I went on to get a BS in math (and comp sci) so I wasn't too scarred from that experience (I am a bit scarred by my whole elementary school experience, but that's another story!)