The effectiveness of direct instruction for teaching language to children with autism spectrum disorders: identifying materials.

Three elementary students with autism learned to name the stuff objects are made of.

The teacher used a Direct Instruction language program. Each lesson built on the last. The team tracked progress with a changing-criterion design.

All three children improved. They could look at a cup and say “plastic” or touch a chain and say “metal.”

The gains happened fast and stayed. Skills rose each time the mastery bar moved.

Azevedo et al. (2025) got even bigger language jumps in younger kids using PROsyntax, not DI. Their preschoolers gained full syntax, while Ganz et al. (2009) taught just one skill set. The two studies line up: both show structured language lessons work for autistic learners.

Slocum et al. (2021) explain why DI worked here. Their paper says careful content mapping makes DI powerful. Ganz et al. (2009) is a live example of that design in action.

Campbell et al. (2024) and Ferguson et al. (2020) also teach language, but they use telehealth DTT with instructive feedback. They match the single-case style and positive results, yet show you can get similar gains online with a different method.

You now have a ready-made DI sequence for teaching object materials. Plug it into small-group rotations or 1:1 sessions. Track each learner with a clear mastery chart. If a child stalls, revisit the Slocum content-mapping steps to spot missing links.