Any simple Python GUI projects for beginner/novice programming students?
In my experience, good introductory programming courses meet three overarching goals:


Empower students to create simple programs outside of the scope of the class by giving them the technical skills and the practice to begin being independent. This includes teaching the basics of one usable language. 
Inspire students to continue learning and using their skills once the class ends (independently and/or by signing up for the next class in the sequence).
Prepare students for the next step in their learning. In many cases, this means that certain topics and concepts must be covered so that students can enter the next class at the correct level. It should also include giving students practice with the skills needed for basic independent learning including debugging, googling to find solutions to problems, and initial exposure to reading and utilizing documentation.


It sounds like you have seen issues with goal number two, where your students do not feel inspired. However, I am concerned that introducing your introductory students to GUI building right off the bat will jeopardize goal number one. GUI has a lot of overhead, and as you said, your students will not understand what they are doing and will be frustrated by their inability to build anything without heavy guidance/pre-built pieces.

My suggestion is to strike a middle balance. Have them build command line applications that they fully understand, but that are interesting or useful in some way. Better yet, give them some choice in which projects to tackle so that they are more invested.

Here are some neat things that students of mine have built in the command line without any OOP:


Guess the Number Game (the computer generates a number and tells the user if they are too high or too low)
Fortune Teller Games (using arrays and randomization)
Personality Quiz
Hangman Game
Random Name Generator
Text Based Adventure
Reverse Guess the Number Game (The user picks a number and the computer has to guess. This is a great jumping off point for first introducing the concept of an algorithm, since the program needs to make "smart" decisions.)
Minesweeper, battleship, connect four, etc. are great for 2D arrays/lists when you get there
Flash Card Application (students can even actually use this to study for tests for other classes!)
Calculator (if that's too easy, have it do harder math. Can your students build a calculator that solves algebraic equations? Can they make it take derivatives? Solve trig problems? You can apply it to whatever math they likely are learning at the time)
To do list manager
An application that manages a student roster or waitlist for a class


I hope these ideas help!