Many of the easiest words to read have short vowel sounds. There are a number of good phonics books available today for children to practice reading with short vowel sounds. We are not limited to boring phonics books of the past. Starfall has a few free online stories with short vowel sounds.I like to teach children phonics rules to decide if a word has a short vowel sound:
A vowel at the beginning of a short word will usually have a short sound:
at, an, and, in, is, it, on, up
A vowel all alone in the middle of a word will usually have a short sound:
can, ran, man, red, get, him, hit, hot, mom, run, fun
There are rule breakers for the vowel all alone in the middle rule, but they often follow a spelling pattern.
old - cold, hold, told, mold, sold
ild - wild, child, mild
igh - light, high, sigh
ind - find, grind, wind, rind
I think the human brain is like a computer. I like to teach rules and patterns, so readers can allow their brains to decode words like a computer. I also like to teach rule breakers, so a child can try to follow the rules and change a sound or two in a word to make it make sense while reading.
Beginning readers are just learning the rules to reading. Joanne Meier wrote an article for Reading Rockets called How to Read with a Beginning Reader that is a must read for anyone supporting a beginning reader.