You could do a custom field that only shows up on those tickets. This KB article might help:

Good morning ​@MaryReed as ​@AMeyer Greendale Schools said using custom fields is the way to achiev this! The KB article they added will guide you along the way if you are brand new to them, but I will attach some screen shots of one I made showing you what it would like. 

1. Create the custom field and made sure the Visible to Requestor and Required boxes are checked. 

   

2. Go into the ticketing tab and add your newly created custom field to a ticket, for the filter select model, and then select all of your districts chromebooks. 

   

3. Now when someone opens a ticket under that model of chromebook, this will appear on the ticket AND be required to be added before they can submit the ticket!

   

Hopefully this helps, and have a wonderful rest of your day!

​@MaryReed We also have the ability to choose what fields are required when creating and importing assets. This would apply to all assets, not granularly per asset type, model category, or individual models.
 

You can find it in Admin > Required Fields: