Together with Samuel Lelièvre (Orsay) and Marc Pouget (Nancy), we supervise undergrad research internships that build on illustration projects to build up understanding of more or less classical mathematical themes. The input is an easily accessible math paper, together with one or several existing mathematical objects, while the expected output is the usual research internship report and the less usual mathematical object. I will talk about three undergrad projects I co-supervised and whose output we really appreciated, both in terms of the objects produced and the understanding we've seen building up among the students: a five-maximal coloring of a paper flat torus by Djatil Krichenane and Alix Kremer; the tiling by right-angled regular pentagons and its dual by Voltaire Brossard; the modular Hilbert curve marble slide by Paul Rémy. All these objects have already successfully been used in outreach -- specially the giant Hilbert marble slide is a huge, huge success. https://www.imaginary.org/hands-on/hilbert-marble-run