This is a colorful poster set to teach and remind your students how to code/mark long and short vowels. There are two versions of each poster: one asking students to "mark" the vowels and one asking them to "code." This way, no matter what terminology you use, you're covered.
Teaching tip: Breve can be pronounced with a long or short /e/, but go with short /e/ since it reinforces the fact that you use it with short vowels. Similarly, Macron can be pronounced with a long or short /a/, but go with the long /a/ since it reinforces the fact that you use it with long vowels!