由於電腦科技的創新，使程式設計者能很容易地開發電子物件，這使研究者開始研究設計一種在電腦上使用的教具－虛擬教具(virtual manipulatives)。這是一種結合實體教具及電腦科技且適合國小學生使用於數學學習的科技輔具。虛擬教具可以像視覺圖形表徵一樣豐富學生的視覺印象，也可以像操弄具體物表徵一樣，這對無法將抽象的數學符號和具體經驗或視覺影像相連結的特殊學生學習有很大的幫助。此外虛擬教具還具有不佔空間、容易複製、分享，課堂上易於整理等優點，也是傳統實體教具所不及的。本文旨在介紹一個由國內研究團隊所合作開發的虛擬教具－萬用揭示板，以使更多特教老師了解這個虛擬數學教具的功能，並能有效地應用於數學的教學。

Recently, an idea to create "virtual manipulatives" was proposed by Moyer, Bolyard & Spikell (2002) to present opportunities for constructing mathematical knowledge. This is an exciting technology for use in teaching mathematics in elementary schools. Virtual manipulatives are often exact visual replicas of concrete manipulates, and are placed on the Internet as applets. Children can use the computer mouse to manipulate the images. These creations are a result of innovations in computer technology that allow programmers to create electronic objects. It is specifically useful for those students who have difficulties in connecting abstract mathematics symbols and concrete experience. In this article, an instructional tool, Magic Board, was introduced for special education teachers to use in class. It is hoped that more teachers will enjoy the use of this tool to integrate technology into their mathematics teaching.