You are not providing sufficient information to answer your question. Do you get an error message?
Here are a few things to consider:
You are on a school network. Is the network blocking ports 8001 and 8004? Those ports have to be available for App Inventor to work. Your apps might compile if you use a non school wifi network. You might try that.
The crashing could be an issue with your browser. Instead of compiling with Chrome, try Firefox.
This could be an issue with your Blocks not being set up properly. If you create a simple Project, just start a new Project and place a Button on the Designer. That is all. Now try to create an aia or compile. What happens? If the simple Project works, there is probably an issue with your existing Project.
What are you naming your Project? Are you naming it in hanzi (汉字/漢字) or using the Latin alphabet? If you use hanzi, try naming the Project and AppName (in the Screen1 Desisgner Properties) using the Latin alphabet. Some times, App Inventor cannot handle unusual characters.
Does any of this help?
Regards,
Steve