This weekend, more than a thousand middle and high school students descended on Stanford campus to take part in Splash, a semiannual, two-day event run by Stanford Educational Studies Program that offers specialized classes taught by Stanford students and faculty.

The 257 classes this year included options in sciences, arts, mathematics and engineering and hobbies. Offerings ranged from “How Your Brain Lies To You, and How To Think More Clearly” to “To Hell with Volunteering” to “The Art of Hair Curling with a Hair Straightener.”

“As a core group we don’t dictate what gets taught,” said Scott Meyer, a Splash participant at M.I.T. and one of the program’s initiators at Stanford. “It’s kind of whatever gets offered to us.”

The most popular classes are “a mix between the things that you would assume to be popular and the truly random,” said physics graduate student Michael Shaw, a co-founder and director of the program at Stanford. “There was a student last Splash who was signed up for ice cream making, which is one of the hardest classes to get into, and she cut that class to go to a series of physics lectures.”

An especially popular class, which Shaw teaches every year, is “On Black Holes, Singularities and the Event Horizon: A Journey into the Abyss,” which enrolls about 120 students per session.

“He has figured out the formula for what gets those kids to come,” Meyer said.

Enrollment this time reached 1,400 students, the largest number ever among the West coast campuses that run Splash programs and the first time Stanford topped 1,000. Although final attendance figures are not in yet, Shaw predicts about 80 percent participation.

Despite the popularity of the program, Splash faces a number of challenges every year. Registration has been front-loaded — in fact, the program had 600 registered participants within six hours of opening its online system — but more volunteers from Stanford, especially undergraduates, are needed to help with the program, according to Ben Shank, a fourth-year physics grad student and Splash’s financial manager for the last three years.

“We are teacher-limited,” Shank said. “We need more Stanford students to help us deal with high school interest.”

Shank said the program is interested in pursuing collaboration with more Stanford departments in order to increase class variety and offerings. For example, piano classes were offered for the first time this year as a result of collaboration with Braun Music Center.

Regardless of the challenges, the future remains promising for Splash. Enrollment is growing at 50 percent per year, and students are coming from as far as Reno and San Diego.

“We constantly get barraged with people saying, ‘Why didn’t we hear about this? Why didn’t you tell us sooner?’” Meyer said. “And we’re making all the effort we can.”

Splash co-president Dena Leeman, a third-year graduate student in cancer biology, said one of the most rewarding aspects of the program was the positive feedback received from students brought in from underprivileged communities.

“A lot of them have never seen a college campus before or have never been in classes taught hands-on,” Leeman said. “Kids said they enjoyed learning for the first time, or considered for the first time going to college…we’re hoping to find more money for that kind of outreach.”

Correction: In an early version of this story, The Daily misspelled Leeman’s first name. The correct spelling is Dena Leeman.