Student facing lagging issue when create the project in 3D environment

Hi ,
I have enable hardware acceleration on browser setting, when I access my student project but the site is lagging. The student using “building” in the library to setup the whole environment and attached alot of pictures in the space.
I don’t understand what can cause the lagging?
Could this due to Cospace server performance issue?

May I ask any solution to improve the lagging issue?

Here is the project link. CoSpaces Edu :: Group assignment
Here is the project link in edit mode. CoSpaces Edu: Make AR & VR in the classroom

There is too many items so the program needs to handle a lot of software.

Unfortunately because of the number of items and assets in the program it is struggling to load everything and slowing the program down cause the lag and performance issues. It might be worth going through the program and take out some of the items you don’t necessarily need and then try and re-open the cospace and see if the lag is reduced.
You should find an optimal point that allows you to keep most while keep the speed smoother.
Hope this helps.