In Kindergarten, our RTI focus is on CVC words which are consonant/vowel/consonant words.

Such as:  cat, mop, hip, leg, bug, etc.

The student are learning how to tap out each individual sound in each word.  The vowels can be tricky especially the vowels e, i, and u.  These vowels tend to sound more alike which can make it a little harder for the students to recognize.  It is important to go over the vowel sounds frequently so they can distinguish the different sounds.

Such as:  I -  itch "i"  (lower case i)  

                E -  Ed   "e" (lower case e)

                U -  up   "u" (lower case u)

This will help them with determining which vowel is in the word.