My School DC made one honest school ranking replace dozens of lotteries

Before 2014, DC families faced a tangle of separate processes: DCPS had out-of-boundary, pre-K and selective high-school processes, while charter schools ran their own applications and lotteries. That rewarded parents who could track many deadlines and hedge across schools.

My School DC turned that maze into one common application and lottery. Families listed schools in preference order, and participating schools accepted only the common application. The algorithm then tried to match each child to the highest-ranked available option rather than handing a family multiple seats.

The matching engine was a deferred-acceptance model developed for My School DC by IIPSC, based on Al Roth's Nobel-winning market-design work. DC PCSB told families the important rule: rank schools in true order, and applying early gives no advantage.

In the second year, My School DC received 20,349 applications for more than 200 schools. The lottery matched 14,592 students at release, a 72% match rate, and 85% of matched students received one of their top three choices.

Make honesty the best strategy

One application removed the administrative advantage of families who could manage many lotteries.

Deferred acceptance made truthful ranking safer than strategic ordering.

A single offer freed seats that would otherwise be held by the same child in multiple schools.

Central waitlist visibility reduced the old scramble of calling schools one by one.

When a choice system makes users game timing and paperwork, merge the queues and design the algorithm so truthful ranking is the dominant behavior.

My School DC became the normal application path for participating DCPS and public charter schools serving PK3 through grade 12. The system still tells families to rank schools in true order and maintains public lottery data by year, ward and grade.