Fill the ten, then count the rest
In a problem such as 8 + 5, the first frame has two empty spaces. Two of the blue counters finish that frame, so the first part becomes 10. The other three blue counters stay outside. The picture turns 8 + 5 into 10 + 3 without asking a child to memorize a trick.
This activity keeps each decision visible: find the empty spaces, move the counters, count the leftovers, and place the leftover number in the equation. That sequence is the meaning of making a ten.
Every randomized problem starts with 6, 7, 8, or 9 red counters, so the first ten-frame is close to full. The second addend never contains more than ten blue counters, and the complete sum never exceeds 20. That keeps both groups inside two tidy rows while preserving the important teen-number examples.