A little rundown of how I do the alphabet for 4th grade (Let's Try 2 Unit 6):
-We do the alphabet 3rd (after Unit 1 - Hello, world! and Unit 2 - Let's play cards).
-We do 5 letters a week over 5 weeks (6 letters for the last UuVvWwXxYyZz)
-First, I explain the difference between letter names, which I call 名前読み (namae-yomi) - ay, bee, see, dee, and letter sounds/phonics, which I call 音読み (oto-yomi) - ah, buh, ck, du. When explaining this, I compare it to how Japanese characters have kun-yomi and on-yomi.
->My 4th graders already did this as 3rd graders so this is just reinforcement.
-Then we sing the ABC song (namae-yomi), the chants, and practice the 5 letter names for that day
-Then we do hatsuon-taisou (oto-yomi) and practice the corresponding letter sounds for that day (ah ah apple, buh buh banana, ck ck cat)
--->It's quite long, so we'll only go up to the letters we've practiced (just 5 the first day, 10 the second, etc.)
-Here's the link to hatsuon-taisou, shout out to @japanalt for originally posting it (https://drive.google.com/drive/folders/1sgC8kZddUy0J8nAnhr22PGpoUoHNGSWN)
-I explain how English has 2 types of letters (uppercase and lowercase), and when we use each
-I hand out the letter-writing worksheet, we practice writing each letter uppercase and lowercase and saying its namae-yomi and oto-yomi
-They do the little phonics quiz at the bottom (I say the word, they write the missing letter)
-We play a game using the corresponding letters where they have to write and simultaneously say either namae-yomi or oto-yomi or both
I've been doing this for 3 years now and find that my current 5th/6th graders have much higher reading/writing skills than their counterparts when I first arrived. I think doing the alphabet/phonics early on in the year, taking 5 weeks to go through 5 letters at a time sequentially, and then reinforcing it throughout the year builds a stronger foundation. Let me know if you have any thoughts in the comments, I hope this helps.