Here's a breakdown of the phonemes present in a popular tongue twister. I am not a linguist, speech language pathologist, or anything else with an 'ist' on the end, so this should be considered a rather crude analysis. Still, I thought it might help me be more intentional about what sounds I'm strengthening in my classroom.
I am still learning about the phonetic alphabet. For this post, I am using this English phoneme chart. I am open to information and advice about how I might refine my knowledge. In this post, I will use my best approximation of the symbol on the chart and also provide a word that exemplifies the sound I'm referring to. /e/ means 'e as in pet', for example. The number behind the phoneme show us how many times it appeared in the passage.
OK, we'll start with a classic:
Breakdown

/h/ 'hat': 1
/au/ 'cow': 1
/m/ 'man': 1
/^/ 'luck' : 5
/tf/ 'chop': 5
/w/ 'wet': 4
/u/ 'good': 6
/d/ 'door': 6
/k/ 'cat': 6
/ago/ 'ago': 2
/I/ 'pit': 1
/f/ 'fan': 1
So there you have it! I don't expect this be a revelation to you, but I think that if we had many rhymes and tongue twisters broken down in this way, we would know where to turn when we encounter students struggling with certain sounds.