These are quick and fun and free ABC blocks.
They go with a woods/camping themed unit that is perfect for Fall. We cut the slices from a large branch and I just lightly sanded the edges with a sanding block. It took about 5 minutes to do all of them - that's it. They were pretty smooth. I used a Sharpie to print the capital letters on one side and the lower case on the opposite side. Took maybe 10 minutes to do that.
You can see the mixture of upper and lower case letters.
Then you have a wonderful, tactile set of ABC manipulatives for your camping/outdoor unit. You can make extra vowels if you wish. I also think that it would be fun to make some story "stones" out of the wood slices for the unit. You could draw simple shapes like trees, tents and woodland animals to use as story prompts in conjunction with the unit. Or leave some blank and use as blocks in the block center or cut enough for everyone to write the letters of their own names on a set- after all the slices are free and take just minutes to cut!!