The Zoom application and it's updates can be installed directly from their website (https://zoom.us/download (Links to an external site.)) if you follow the instructions in this video:
If you're installing Zoom for the first time, you will click the "Sign up, it's free" button at the top right to create a username and account (Use your school email address to create the account)
If you can't see the video, click sign in and use your school email address and password
If you have trouble viewing the video above, or if you'd rather read step-by-step instructions, follow the steps below:
1. Go to zoom.us in your browser
2. If you've created an account in the past, you can click on "sign in." If you've never created a Zoom account, click on "Sign up, it's free"
If you have previously created an account, skip to step 8
3. After entering your birthday, enter your school email address and click "sign up"
4. Now check your school email in Outlook or at outlook.office365.com 
5. Find the email from Zoom and click the "Activate Account" button
5. You'll be taken back to the Zoom website where you'll enter your name and create a password. The answer to the question about signing up on behalf of a school is "no"
6. You can skip this step
7. And you can ignore this step, since you won't be starting your own meetings. You'll be joining your teacher's meetings. Now that you have an account, let's download the Zoom application.
8. To download Zoom, first go to zoom.us/download
9. Click the "download" button under "Zoom client for meetings" (your Mac does not have a silicon chip)
10. Go to your downloads folder and open the package file that downloaded named "Zoom.pkg"