That also never happened to me - but I understand you, @AllisonR3333 . If you feel disappointed that you can't spend breaks talking to that friend,  greet each other saying 'Hi' every morning when you come to school or maybe even sit next to each other in the classroom anymore - that's normal & natural - & you have the right for the 'feeling of loss' you're most probably experiencing now. 

You haven't told me if that friend is changing 'just school' - & staying in the same house or changing the house also - so I will try to answer both options: 

*If my friend changed school - but stayed in the same house that would be close enough to My House to visit each other - We would still meet after school ( & I would ask that friend to collect funny stories that happened in their new school - cause something funny can happen everyday - & it gets Double Funny & possible to laugh at it again when you can tell your friend about it some time later.

So I would collect 'funny school stories' from their 'old school I would still be going to' as well - & then when we found time to meet after school - we would ask each other 'How was your school?' ... 'Good! :) - This & this happened today... - & How was Your School? :) ' & we would laugh at our funny school stories together - & then talk or do the things we liked before they changed school - to make their school change 'as painless as possible' - at least they would keep some daily routine: that is 'talking to a friend they know & spending time together' - which would help them 'feel safe & deal with the change better' :) )

**If that friend also moved to another house: 

- & it would be too far to visit each other as often as we want to or not possible anymore - we would use modern technology ( like mobiles, skype or online chat on websites we're both logged in to < so if they don't have Wattpad or any other social media you're using - you can ask that friend to join it, I'm sure they would agree to still have a chance to communicate with you everyday :) >  ) to stay in touch with each other.

I hope that my advice was helpful, @AllisonR3333 ! 😊

- I'm keeping My Fingers Crossed for your Friend's Good start in Their New School ! :) 

( *& one more tip: If this friend makes some new friends there - don't be jealous! - Because I'm sure you'll always stay important to him/her - & if your Friendship is strong enough: No Place Change can Change THAT!  ^_^ 👍)