Engineered living materials are functional materials that incorporate living components within a polymer matrix. Gaining insight into the physical, chemical, and biological factors that influence the spatial organization and growth of cells within this matrix is essential for predicting and enhancing the functionality and responsiveness of engineered living materials. We investigate the motility, growth, spatial distribution, and photosynthetic activity of the eukaryotic microalga Chlamydomonas reinhardtii within a hydrogel matrix. 3D printing allows us to define the overall shape of the biohybrid hydrogel, while cell growth and localization are directed by light exposure and carbon source availability. I will present a strategy for guiding cell growth to boost the productivity of photosynthetic living materials, drawing inspiration from adaptive mechanisms found in multicellular plant leaves. Additionally, I will share approaches that we developed to enable large-scale, reversible, light-controlled dynamic shape changes in the microalgal hydrogel.