Recently, chimeric antigen receptor (CAR) T-cell therapy has begun to be used for solid tumors such as glioblastoma multiforme. Pediatric malignant brain tumors patients develop extensive long-term morbidity of intensive multimodal curative treatment. CAR T-cells treatments could potentially create favorable outcomes and reduce the toxicity of current treatment. T-cell infiltration of solid tumors has been associated with good prognosis. A largely overlooked area of CAR T-cell therapy targeting solid tumors is enhancing the ability of CAR T-cells to migrate and infiltrate solid tumors. A potential reason could be lack of standard in vitro assays which can screen for genetic modifications that result in enhanced T-cell migration in CAR T-cell therapies. We report a novel coculture assay using 3D tumor spheroids cocultured with T-cells to analyze the effect of activating CAR T-cell interventions on cell migration by a simple imaging based readout. This assay can be applied to several different kinds of cancer cell lines in higher throughput as well as toward measuring the efficiency of currently available CAR T-cell therapies in untested solid tumors.