The school is holding an open house for alumni from 11am to 3pm.
The southwest Houston school has graduated more than 37,000 students, including some who have made great contributions to the city of Houston, like former Mayor Fred Hofeinz and singer Tommy Tune.
More than a thousand former Lamar students are expected to attend the open house.
There will be a pep rally and then former Governor Mark White and former press secretary and KTRK political analyst Peter Roussel will speak.
