Many students think of electrons and photons as classical particles
Misconception
For example, students may think that all objects from the microscopic world are basically material particles with mass, following definite trajectories.
Even after quantum mechanics teaching, many students still describe an electron as a classical particle.
Resources to Address This

The idea of wavelike behaviour being associated with electrons and the Complementary principle is described by this teaching guidance.
It supports a discussion about whether there are separate particles or waves which are used to describe reality, or whether behaviour is more complex than this.
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This resource provides a lesson outline and support materials for discussing spectra and energy levels. It can be used to discuss the interaction of electrons with photons leading to the idea of quantisation of energy in electrons. A more general idea of quantisation and the relationship of frequency and photon energy is also discussed.
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A practical activity can be used to show diffraction of electrons in an electron diffraction tube. The resulting electrons diffraction patterns can be compared to the diffraction of light through a grating, showing wavelike behaviour. The energy of the electrons can be varied to show how this effects the diffraction pattern, introducing the idea of a de Broglie wavelength.
A video is also provided here to explain how the electron diffraction tube is set up and operated to give clear results.
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The diffraction of electrons and light should be compared to introduce the idea of waveparticle duality. Particle momentum and wavelength are linked through the de Broglie equation.
Students can practice using the de Broglie equation and learn how to interpret electron diffraction patterns.
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This physics narrative is part of the “multiple contributions” approach to describing the concept of interference. It discusses ways of explaining diffraction patterns in terms of vibrations.
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References
 Greca, I. M. and Freire Jr., O., () Does an Emphasis on the Concept of Quantum States Enhance Students' Understanding of Quantum Mechanics? Science & Education, 12, 541557.