This paper reports a mixed-methods study at a public university in Colombia. It describes the classroom assessment practices and challenges of 75 novice foreign language teachers. To gather the quantitative data, the participants completed an online survey. For the qualitative data, 11 key informants participated in one-on-one online interviews. Findings revealed that novice teachers predominantly used summative assessment in the classroom and aligned their assessment instruments to large-scale tests. Moreover, novice teachers faced many challenges with classroom assessment, including determining how to assess their students, developing assessment instruments, and interpreting and using assessment scores to inform teaching and learning. In conclusion, novice teachers need more knowledge, skills, and support to handle daily assessment-related tasks.