Squishy Bag - A tactile/multisensory approach to pre-writing and writing skills. Things you need - Gallon size Ziploc bag, glitter (optional), food coloring, hair gel (dollar store) I like this better than paint.
Homemade kinetic sand- Squishy, mold-able, & lots of fun! Why waste your money on the store bought stuff when you can easily make this recipe at home! 6 cups of play sand 1 & cups of corn starch 2 tsp of dish soap cup of water
Sensory mats - "Goo bags - recipe for goo. I've had it suggested to use an entire bottle of dollar store hair gel, but this is probably just as inexpensive, and you can make whatever VIBRANT colours you want." Letter writing with fingers or Q-tips.