Differences in accounting for trading securities versus available-for-sale securities is often confusing to students. SFAS No. 115, Accounting for Certain Investments in Debt and Equity Securities (FASB, 1993), SFAS No. 130, Reporting Comprehensive Income (FASB, 1998), and the presentation of investments in intermediate financial accounting textbooks provide limited guidance for preparing useful classroom examples. Moreover, little mention is given in textbooks to the Statements' explicit shift in measurement theory for security investments from historical cost to current cost. In this paper, we provide examples of the accounting treatment, journal entries, and financial statement preparation for trading and available-for-sale investment portfolios. Both debt and equity portfolios are used to illustrate the accounting for gains and losses (holding and realized), and the related financial statement presentation. The examples also provide an introduction to the relationship between net income and comprehensive income.