Paid $35 each (yes I know $35 too much) for a couple of old tyronseas just over a year ago to teach my kids on, they preferred them to the wider shorter boards said they go faster. They have been doing ok considering we don't get out much.
They have been using an ezzy kids rig and a Gaastra 3.4 maverick. The 3 of us were out sailing around a few weeks ago, boys on tyronseas and me on jp sup with a 4.2 ka wave sail, they blew me away upwind.
Old boards are ok for teaching kids, but beware if a big person (aka dad) takes them out in stronger winds, bigger sail and chop.

They break.

in half.