Photo of Steve Jobs looking down on stage, with bubble overlay showing homemade science fair project. Justin Sullivan/Getty Images, RRAuction.com

Apple devotees marked the company’s 50th anniversary earlier this month by shelling out thousands for everything from company memorabilia to a stained glass window suncatcher that hung in Steve Jobs’s childhood bedroom.

But one very personal item from Jobs’s stepbrother John Chovanec’s own collection netted over $30,000 — his 8th grade science project. As the listing reveals, this project remained at his childhood home for decades — even after his father died — despite repeated requests from both his stepmother and Chovanec to take it home.

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Eventually, Chovanec took ownership, carefully “safeguarding this rare artifact of Jobs’s early technical curiosity and family history.”

Along with 148 other items up for auction, Jobs’s handmade project on the silicon-controlled rectifier sold to the highest bidder on August 20 for $34,375.

An eye-catching report with instructions for judges

True to form, the Jobs-designed science fair project is eye-catching. With a backer made of thin wood and a curved wooden banner asking onlookers “What is the SCR?,” the project has typed descriptions and explanations stapled to the backer as well as two test circuits showcasing the functionality of the semiconductor devices, which are used to control electrical power.

There’s also a note to the judges, urging them to “please unplug!” the circuit after using it. (Even in eighth grade, Jobs was apparently a control freak.)

A written report, bound in a blue folder with hand stenciling, was also included with the item.

“For my science project I have selected to do research and experiment with the silicon-controlled rectifier,” Jobs wrote in the report.

“I am making a circuit that demonstrates the basic properties and characteristics of this semiconductor. The silicon-controlled rectifier is the most widely used of a family of four-layer semi-conducter power devices that exhibit regenerative or latching-type switching action. The silicon-controlled rectifier is widely known as the SCR. International standards describe the complete family of semiconducter regenerative switches under the name Thyristors.”

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Other memorabilia drew eager bidders

While the science project has the most direct ties to Jobs, Apple collectors have a lot to choose from when it comes to company-focused memorabilia.

Some of those are already commanding a high price. An Apple-1 computer in a Smith-Corona typewriter case, with the original documentation, went for $499,363. And an autographed Jobs business card sold for $156,658, more than doubling the pre-auction estimate.

Other items included rare Apple devices, a Steve Wozniak-signed Macintosh classic and some Jobs-signed 1976 checks from the Apple account.

The science project sold in the second half of a two-part auction of Apple memorabilia, demonstrating company loyalists are willing to spend heavily to own a piece of Apple and Jobs’ history.

In the first round, the first check issued by Apple, which was signed by both Jobs and Wozniak, was expected to sell for half a million dollars. By the time bidding ended, it went for $2.4 million. And an Apple-1 prototype board, which was the first-known one on fiberglass, sold for $2.75 million. — with files from Sigrid Forberg

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This article originally appeared on Moneywise.com under the title: Steve Jobs’ 8th grade science project sells for $34,375 as rare Apple memorabilia fetches millions at auction

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