Numerous websites offering tips on reading instruction refer to the digraph ch as a “blend.”
The phonogram ch is not a blend.
A blend is a letter combination that represents two distinct sounds run together. Here are some true “blends”: bl, br, cl, cr, dr, fl, fr, gl, gr pl, pr, sl, sm, st
Each of these letter combinations represent two distinct sounds run together to pronounce a word.
Here are some words that contain the blends listed above:
black, bring, clam, creep, drag, flow, French, glance, grade, plan, prince, slide, small, stand.
The bl in black represents the sounds of b and l. The fr in French represents the sounds of f and r.
Ch does not work in the same way.
Ch is a digraph: a spelling symbol represented by two letters, but representing one sound.
The digraph ch is not a “blend” because it does not represent the sounds of c and h run together. Ch in chicken represents a sound that is different from either c or h. It represents a sound made by the tongue moving on the palate. Ch in chrome represents the sound of the letter k. Ch in chef represents the sound usually spelled sh (another digraph and not a blend).
The most common sound represented by the diagraph ch is the /tch/ sound heard in church, chance, and inch.
Ch represents the sound /k/ in words of Greek origin: Christmas, chronicle, and archaeology.
Ch represents the sound /sh/ in certain French borrowings like chef, chauffeur, and chamois.
Instead of confusing beginning readers by telling them that ch is a “blend,” tell them that ch is an “extra letter.” And teach them the three sounds it stands for: /tch/, /k/, /sh/.