arXiv:2611.13386v1 Announce Type: new Abstract: Designing machine learning (ML) experiments requires beginners to plan a methodologically sound workflow and implement it in a concrete environment. We evaluated two forms of support in two within-participant studies with 18 predominantly technically trained participants: mlguide, which provides structured, evidence- backed guidance for workflow design, and AI Sandbox, a visual no-code environment for workflow implementation. After using mlguide, participants produced better high-level workflow designs, but their scores on a quiz about specific methodological choices did not improve significantly. Compared with Google Colab, AI Sandbox received higher hedonic user experience ratings, while perceived workload and acceptance did not differ significantly. These findings suggest that different forms of interactive support help with differ- ent aspects of beginner ML experimentation. The paper contributes a reusable evaluation task with instructions, a modified dataset, and a quiz, as well as empirical evidence on structured guidance for workflow design and on the experience of implementing workflows in visual and notebook-based environments.