SQL Server 2008 : force user to change password at next login
If you are creating a new login you have that option of " enforcing users to change the password at next login" from windows policies.
Therefore for To force a user to change password at next login, the sql login should be created with "Enforce Password policy" checked.

If you go back into this newly created login later, and look at the boxes, only 2 options are available to be checked. The “User must change password at next login” is grayed out.


  In order to access the box and force a password change, you need to
  change the password. The reason is that if the account is compromised,
  the hacker should not be the one to set a new password. The security
  model assumes the administrator can contact the legitimate owner
  offline and give them the new password.


You can refer here for same as well.