Yes, SCOTUS only did away with state sponsored prayer. However, the implementation of that decision tends to go farther. For example, prayer must be done privately, so most overt prayer is banned. Some schools have/tried banning religious items that would be overt, such as rosaries. So it goes farther than simply banning state sponsored prayer and becomes a 1st Ammendment issue if students are being told they can pray, but must not speak it.

For the gun topic. Some schools removed firearm education from the curriculum and even as an elective. So it's not an outright ban but a defacto one. Even when there is agreement that safety should be taught, there is a lot of debate about using a program designed by gun control groups or gun rights groups. What we also have seen are students getting in trouble for off-campus, non-threatening, lawful use of firearms. These discaplinary events are very egregious, and the schools has no basis for their actions in these cases. The only assumption that can be made is that the people making those decisions politically oppose that to the point that they are ignorant of the laws and overreact.

The issue of gun images is not a second amendment issue, but a first. School dress codes are only allowed to ban general things that would interfere with education. However, guns are usually explicitly called out. Not to mention the display of gun imagery in a manner that doesn't condone violence would not interfere with education.

"it still pales compared to what the right is attempting currently."

What is that?