• LogicTools on Datascientia local instance of the Logic Tools, where you can have PL and FOL problems solved. The tools are more relevant for PL than for FOL.
• Tree Proof Generator builds Tableaux for PL and FOL.

You might try using these materials to get a different approach to explaining the topics we cover in the course. Notice that these materials might not cover topics we cover in CL-2020 and, viceversa, explore topics we are not covering in this course.

• Introduction to AI at Cornell as a lesson dedicated to FOL, which includes a very short tutorial on Prolog.
• First-Order Logic -Syntax, Semantics, Resolution is another introduction to FOL in the form of slides.
• The Seminar on Automated Reasoning at TUM has material to read on various topics, including Tableaux for FOL.
• The Logic Notes pages focuses on (natural) deduction, but it has a lesson on Tableaux.
• First-Order Tableau is a chapter from a book, probably, covering Tableaux for FOL.
• Tableeuax for first order logic at the University of Roma is a step-by-step example of Tableaux with term substitution. Part of the Planning and reasoning course by Paolo Liberatore.

A very detailed and clear discussion about the formalization of constraints on terms satisfying a formula (exactly …, at most …, execpt …):

• More about Quantification at the University of Washington (Full set of lecture notes).

• Introduction to Logic is a blog and course on logic, with highlights on logical fallacies in informal reasoning. It also has various interesting exercises on informal to formal: I2F for PL and I2F for FOL.
• Exercises on satisfiability and Exercises on PL, FOL, Set Theory
• The Logic in Computer Science (COMP118) course has various exercises, which you can find, for instance, here: Lecture 4, Tutorial 1, Test 1. If you are interested in the topic, you might also have a look at the Material page, where you can find some nice resources.

The following focus on Modal Logic and Description Logic:

• Mathematical Logic Exercises at DISI covers everything, including ML and DL
• Description Logic at TUD
• DL Exercises at Libre Books
• Modal Logics at UNIBZ
• The Little Logic Book at Calvin
• Phil 511 at UMASS, Exercises see also: http://people.umass.edu/klement/511/
• Basic Modal Logic

• This is useful only for Adolfo, since he always forgets where the course lives: https://didatticaonline.unitn.it/dol/enrol/index.php?id=24456

A very nice website is:

• Open Logic Project which collects many resources and textbooks covering logic.

They might have exercises at the end of each chapter:

• Introduction to Mathematical Logic (Elliott Mendelson)
• A Concise IntroductiontoMathematical Logic (Wolfgang Rautenberg)