1. Considering Sidwalks on Concord Avenue: Lexington's Engineering Division is studying the possibility of installing a sidewalk along Concord Avenue from Waltham Street to Spring Street. And, at 7 p.m. tonight at the auditorium at Brookhaven at Lexington, the town will hold a public workshop to solicit input and help refine the design.

2. An Evening with Poet Gregory Orr: At 7 p.m. tonight at Lexington High School, Lexington Community Education will host an evening with Gregory Orr, a poet who is considered by many to be a master of short, lyric free verse and authored 10 collections of poetry. Admission is $10.

3. Today in Public Meetings: Public meetings posted for today on the town website include: the Tree Committee at 7:30 a.m. at the DPW Building; the EDCO Collaborative at 10:30 a.m. at the EDCO Offices in Waltham; the Town Celebrations Committee at 7 p.m. at the Cary Memorial Building; the Permanent Building Committee at 7 p.m. at the DPW Building; the Historical Commission at 7:15 p.m. at the Cary Memorial Building and the Board of Appeals at 7:30 p.m. at the Town Office Building.

4. All Town Orchestra Concert II: This second All-Town Orchestra Concert features the Lexington High School Repertoire and Symphony Orchestras along with the Clarke and Diamond 6th Grade Orchestras, the Clarke 7th and 8th Grade Orchestra, and the 4th grade beginners from Bowman, Bridge and Harrington. The concert begins at 7:30 p.m. tonight at Lexington High.

5. Clouds Part, Weather Warms: Morning clouds should clear to a sunny and warm winter's day, with highs of about 45, according to the National Weather Service, which predicts a clear evening with a low around 26.