Lexington residents have a big decision ahead with December’s vote on the new high school building. A new AI-powered chatbot — built by Lexington High School students — can help answer some of your questions about the project. 

To power the system, the students developed a custom framework that combines Retrieval-Augmented Generation (RAG) with the ReAct (Reasoning and Acting) agentic workflow. Through RAG, the team integrated reports and presentations from the School Building Committee and architects, project submissions, FAQs, and other stakeholder-provided resources into their knowledge base. ReAct complements this by guiding the model through iterative reasoning steps and actions. There are limits to what questions the chatbot can answer — it’s all based on public documents related to the school building project. For more in-depth reporting and analysis, read LexObserver’s extensive coverage in our ongoing LHS Watch series. 

LHS Building Project Chatbot

The chatbot builds on an earlier project, the “LexBudget Chatbot,” which the Observer launched in 2023 in partnership with the Youth STEAM Initiative to help residents better understand the town budget. Some of the same team members went on to create the new LHS Building Project chatbot. The tool is still in its beta phase, and the students are inviting residents to explore it and share feedback.

Team members: Jerry Xu (Project Lead), Justin Wang, Jasmine Gu, Joley Leung (Graphics) Mentors: Wei Ding, Jeannie Lu

Join the Conversation

4 Comments

  1. I asked this chatbot 2 questions (see below). AI is not ready for prime time, since in its 2nd answer, the chatbot ignored the publicly available https://docs.google.com/spreadsheets/d/1PcH2CCi7DjPlKq10Q0ZhS41RU4VY6D9O/edit?usp=sharing&ouid=116971253884586510151&rtpof=true&sd=true spreadsheet I told the chatbot about, or couldn’t deal with its simple arithmetic.
    ~~~~~~~~~~~~~~
    My 1st question: Is it true that Bloom will cost 43% more per square foot and offer 28% less space per student than the new Watertown High School opening next April?

    The chatbot’s answer: The claim that the Bloom design will cost 43% more per square foot and offer 28% less space per student compared to the new Watertown High School is not directly addressed in the available documents. However, the estimated project cost for the Bloom design is $659 million, which includes the school, a renovated and expanded field house, and the Central Administration Offices. The cost per square foot is based on other recent school construction projects in the metro Boston area, adjusted for cost escalation and inflation.

    For more detailed comparisons, you may need to look at specific cost and space metrics for both projects, which are not provided in the current FAQs.

    For further information, you can refer to the Project FAQs.

    My 2nd question: As https://docs.google.com/spreadsheets/d/1PcH2CCi7DjPlKq10Q0ZhS41RU4VY6D9O/edit?gid=223099950#gid=223099950 states, is it true that Bloom will cost 43% more per square foot and offer 28% less space per student than the new Watertown High School opening next April?

    The chatbot’s answer: The claim that the Bloom design will cost 43% more per square foot and offer 28% less space per student than the new Watertown High School is not directly addressed in the available documents. However, the estimated project cost for the Bloom design is approximately $662 million, which includes the school, a renovated and expanded field house, and the Central Administration Offices. The cost per square foot is based on other recent school construction projects in the metro Boston area, adjusted for cost escalation and inflation.

    For more detailed comparisons, you may need to look at specific cost and space metrics for both projects, which are not provided in the current FAQs.

    For further information, you can refer to the Project FAQs and the Preferred Schematic Report.
    ~~~~~~~~~~~~~~
    More interesting to me than this chatbot (which I hope will not make our young students believe in AI, but rather will make them use their brains — for example to check the spreadsheet’s arithmetic and sources) is the fact that no Bloom supporter has shown my findings that Bloom is 43% more expensive than the new Watertown High School, and offers 28% less space per student (as shown in https://docs.google.com/spreadsheets/d/1PcH2CCi7DjPlKq10Q0ZhS41RU4VY6D9O/edit?usp=sharing&ouid=116971253884586510151&rtpof=true&sd=true) to be incorrect.

    1. Hi Mr. Mehr,
      Thank you for testing our chatbot and sharing your feedback. We truly appreciate your engagement and interest.
      To clarify, our chatbot is neutral in position: it does not take sides for or against the new high school building project. It provides responses based on a curated set of official documents in our knowledge base. These materials include reports from the School Building Committee and Dore + Whittier Architects, as well as presentations, project submissions, FAQs, and other resources provided by stakeholder groups. This approach ensures that the chatbot draws from authoritative and verified sources.
      Since our beta release, we’ve received an overwhelming number of responses from residents. Several have suggested adding specific documents. We’ve incorporated a few that we could verify directly from official sources, such as the Lexington Town Website.
      Thus, for your query, the chatbot functioned as designed: it provided an answer based on the official information currently available in its knowledge base, without influence from external or unverified sources.
      If you have further questions or suggestions, please don’t hesitate to contact us at lyst.connect@gmail.com!
      Best,
      Jerry | Project Lead

  2. Dear Patrick,

    Thank you for testing the chatbot and sharing this detailed feedback. We appreciate your careful review and the specific example you provided—it’s extremely valuable as we refine the system.

    The development team is currently looking into this case to understand why the chatbot did not appropriately reference or process the linked spreadsheet in its second response. We will address the issue and follow up with you once we’ve implemented a solution.

    Your input helps strengthen both the chatbot’s accuracy and the students’ learning experience. Thank you again for bringing this to our attention.

    Best regards,
    Wei Ding
    Faculty Mentor, Chatbot Project

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