I put a highlighter into his desk and he's been really into using it for completing his activities this week. He pretty much did no writing with anything but the highlighter.
We also did some shaving cream play this week. He was supposed to write his letters in it but he wasn't interested in that so we just played with it. He really enjoyed the sensory experience. It didn't go so well for my daughter though and we had to call poison control because she ate a handful of it super quickly. Luckily she was fine.