I tried baking in old jars (like pasta sauce jars and jelly jars) unsuccessfully because the top isn't wide enough. But I have these drinking glasses that have a decent thickness and I am wondering if I can bake in them. Will they crack in the oven?

Most drinking glasses are not tempered for oven use. They can shatter if not just crack.

Wide mouth canning jars are really the only thing that works for baking in jars.

Thanks so much! I appreciate the help!