PBS was expecting online streaming of PBS Kids shows for the 2-5 set to be popular when it started late last year; the usage of shows for older kids, 6-plus, which went online earlier, had fluctuated around 2 million video streams a month. They were not prepared for the tots’ appetite: 87.5 million streams in December. PBS kept mum about the number until the press tour and the NETA Conference this week. Station folk broke into applause Wednesday as PBS education chief Rob Lippincott announced the figure. Streaming of the little kids’ programs rises in the evening as the grownups’ NewsHour grabs the TV sets, he said.