My first said her first words at 9 months old, "ba" for ball, bath, and 2-3 more meanings, and made a repeated sound pointing towards the object of interest, sound which cannot be described in words. Before the age of 1 we had amassed over 50 words, most up to 3 syllables, a handful had more. Same for walking, fine motricity, etc. She reads at 5 years old.

My second only started saying single syllable words at 1y10m, started walking similarly later, and isn't able to do at 1y10m most things that my first was already able to do before being 1yo, so the delay between them is higher than 100%, more than double.

Same family, same teaching style, etc, only 3 years apart.

The ability to teach your child to do something depends almost entirely on the child, your teaching abilities don't seem to matter much, they simply copy you. All that matters is that you are present and offer them the attention they need.

Is there any studies out there on adults to see what affect if any there is from learning to read at different ages. I'm not talking about someone who learnt at the age of 12, just the 4-8 age range.

Reading is probably the most important skill for children as a child that struggles to read will later struggle to study and learn anything else as well.

One thing OP didn't address directly is that the most significant lesson of watching our kid on this journey has been learning on a practical level how early individuality and complex reasoning show up. Before I was a parent, I thought kids were blobs where parenting unlocked skills. Since becoming a parent, I've learned that kids, on some level, are experiencing frustrations and joys that are shockingly similar to adults' and that a lot of their development isn't just bits and pieces turning on over time but affirmative effort on their part. I don't know why that should be surprising given we're the same species, but it really struck me that this little person on some level realized he couldn't read, wanted to, and learned. That affected other areas of our parenting, e.g., addressing his frustration as if it were a rational human response to a challenging situation from his perspective rather than irrational childhood reaction. (Note: He's still a child and we don't parent him as if he's an adult, but we have subtly adjusted our approach to be more ... I don't know, respectful of his individual motivations as a thinking, feeling person with comprehensible goals and desires, even if the underlying support infrastructure is still a bit in flux.)

The best teacher is want.

Too many smart parents have smart kids, avoid completely neglecting them, and then talk about how great they are at teaching kids and how stupid The System is for failing to do this. Good on you for being there, and no doubt your effort helped out, but don't kid yourself. Your main contribution here is your DNA.

Dividing classes up by reading level is a major factor in reducing problems in a classroom --- but it's only feasible where the number of classes offered and class sizes and school size/budget allow.

The best school system I ever attended extended that to dividing classes betwixt academic and social --- social classes were attended at one's age level (homeroom, civics/social studies, PE, &c.), while academic classes (math, science, English/reading) were attended at one's ability level, with a 4 grade cap until 8th grade --- after that, the school had faculty who were accredited by a local college and there was a mechanism to either bring professors from that college to the school, or to take students to the college for classes --- it was not uncommon for students to graduate and be simultaneously awarded a BS or BA or BFA along with their high school diploma.

I’m 41 now; AMA.

On the other hand, he finds numbers delightful, can add two digit numbers and knows his multiplication table up to 10, loves squares and square roots, and can do simple algebra problems in his head (equivalent to solving 3x+1=28). He once sat by himself with his blocks for an hour figuring out all the triangular numbers ("step squad" numbers) that he could make with the 200 blocks he had.

I think you just have to try different things and see what the kid latches on to. Lego, drawing, music, whatever. Reading is not the only way to activate your brain, and I think peer pressure is a big part of why kids want to learn to read once they get to school. That and there are just too many ways to be entertained these days (video, audio, toys, etc.) while reading takes true grit.

Note that our language is Hungarian, which is much easier to teach because writing and sounding out words are nearly one-to-one in terms of letters and sounds. The AI part: Phonemic orthography: A writing system in which each letter (or combination of letters) consistently represents a specific sound (phoneme), and each sound is represented by a consistent letter. Hungarian is highly phonemic, meaning you can usually tell how to pronounce a word just by looking at how it's written, and vice versa.

More on-topic - I recommend Grace Llewellyn and John Holt on learning, to anyone. Truly life-changing material. Finally got around to John Holt recently, and am very happy to eventually read his work.

You can't get back the years made painfully lesser by the school systems we put people through - myself included - and you probably can't undo all the damage done, either. But you can face the absurdity of the situation, and try to improve your own mental life, and that of the people in your life.

What's more is that those x hours of tutoring/memorization could've been filled with creative/social/emotional regulation/etc. learning that we know for sure benefits kids at that age.

I remember we learned to read and write in one month in Finnish school. If this did not happen, one was officially classified as retarded (in 1950s). How long it takes average american to achieve errorfree skills?

Grok:... In USA on average, achieving consistent error-free literacy might take 4-6 years of schooling (kindergarten through fourth grade), but this varies widely.

More recently, I’ve been teaching a 3 year old letter sounds and he loves running around finding signs saying “Dad” I found a “duh”. “Duh duh duh!” (For D). Kids really just want to hang out with you so, it’s ok to just throw in some letter sounds or number counting ideas in here and there. You’ll be surprised what they pick up!

I hacked an HTML <table> so that the cards would come out in only two different sizes, and then laminated & cut them. Also simple words like left, right, front, back. I used font attributes to grey out silent letters and oddities like "gh" (this was for English), and I used <small> for the occasional unusually long word.

Then my kid and I played "The Body Parts Game". I shuffle the cards and go thru them one by one. Each card, I ask him to say the word and then point to the body part.

It went really well. It kept a 2yo entertained and he knew he was learning something important.