The sound /ou/ can be spelled two ways: 

vowel team OU, as in “scout”; and, 

vowel team OW, as in “cow”.

Vowel team OU is more commonly used to spell /ou/ when in the middle of a word or syllable than vowel team OW–unlesss followed by consonants N or L. 

If /ou/ is followed by consonants N or L, then OW is used, as in “frown” or “scowl”.

Vowel team OW is more commonly used to spell /ou/ when it is at the end of a word, as in “cow”.

Look at this image and decide how it can help you remember the two Spellings Of /ou/.

Vowel team OU sometimes says /ō/ when followed by GH, as in “dough”.  This is practiced later.

OU also says /ů/, as in “could”. “should”, and “would”, which are learned as sight words.