BLOCK-BASED PROGRAMMING LANGUAGES ARE BECOMING INCREASINGLY COMMON IN INTRODUCTORY COMPUTER SCIENCE CLASSROOMS ACROSS THE K-12 SPECTRUM. ONE JUSTIFICATION FOR THE USE OF BLOCK-BASED ENVIRONMENTS IN FORMAL EDUCATIONAL SETTINGS IS THE IDEA THAT THE CONCEPTS AND PRACTICES DEVELOPED USING THESE INTRODUCTORY TOOLS WILL PREPARE LEARNERS FOR FUTURE COMPUTER SCIENCE LEARNING OPPORTUNITIES. THIS VIEW IS BUILT ON THE ASSUMPTION THAT THE ATTITUDINAL AND CONCEPTUAL LEARNING GAINS MADE WHILE WORKING IN THE INTRODUCTORY BLOCK-BASED ENVIRONMENTS WILL TRANSFER TO CONVENTIONAL TEXT-BASED PROGRAMMING LANGUAGES. TO TEST THIS HYPOTHESIS, THIS PAPER PRESENTS THE RESULTS OF A QUASI-EXPERIMENTAL CLASSROOM STUDY IN WHICH PROGRAMMING NOVICES SPENT FIVE-WEEK USING EITHER A BLOCK-BASED OR TEXT-BASED PROGRAMMING ENVIRONMENT. AFTER FIVE WEEKS IN THE INTRODUCTORY TOOL, STUDENTS TRANSITIONED TO JAVA, A CONVENTIONAL TEXT-BASED PROGRAMMING LANGUAGE. THE STUDY FOLLOWED STUDENTS FOR 10 WEEKS AFTER THE TRANSITION. OVER THE COURSE OF THE 15-WEEK STUDY, ATTITUDINAL AND CONCEPTUAL ASSESSMENTS WERE ADMINISTERED AND STUDENT-AUTHORED PROGRAMS WERE COLLECTED. CONCEPTUAL LEARNING, ATTITUDINAL SHIFTS, AND CHANGES IN PROGRAMMING PRACTICES WERE ANALYZED TO EVALUATE HOW INTRODUCTORY MODALITY IMPACTED LEARNERS AS THEY TRANSITIONED TO A PROFESSIONAL, TEXT-BASED PROGRAMMING LANGUAGE. THE FINDINGS FROM THIS STUDY BUILD ON EARLIER WORK THAT FOUND A DIFFERENCE IN PERFORMANCE ON CONTENT ASSESSMENTS AFTER THE INTRODUCTORY PORTION OF THE STUDY (WEINTROP & WILENSKY, 2017A). THIS PAPER SHOWS THE DIFFERENCE IN CONCEPTUAL LEARNING THAT EMERGED AFTER FIVE WEEKS BETWEEN THE BLOCK-BASED AND TEXT-BASED CONDITIONS FADES AFTER 10 WEEKS IN JAVA. NO DIFFERENCES IN PROGRAMMING PRACTICES WERE FOUND BETWEEN THE TWO CONDITIONS WHILE WORKING IN JAVA. LIKEWISE, DIFFERENCES IN ATTITUDINAL MEASURES THAT EMERGED AFTER WORKING IN THE INTRODUCTORY ENVIRONMENTS ALSO FADED AFTER 10 WEEKS IN JAVA, RESULTING IN NO DIFFERENCE BETWEEN THE CONDITIONS AFTER 15 WEEKS. THE CONTRIBUTION OF THIS WORK IS TO ADVANCE OUR UNDERSTANDING OF THE BENEFITS AND LIMITS OF BLOCK-BASED PROGRAMMING TOOLS IN PREPARING STUDENTS FOR FUTURE COMPUTER SCIENCE LEARNING. THIS PAPER PRESENTS THE FIRST QUASI-EXPERIMENTAL STUDY OF THE TRANSFER OF KNOWLEDGE BETWEEN BLOCK-BASED AND TEXT-BASED ENVIRONMENTS IN A HIGH SCHOOL SETTING. THE LACK OF SIGNIFICANT DIFFERENCES BETWEEN THE TWO INTRODUCTORY PROGRAMMING MODALITIES AFTER LEARNERS TRANSITION TO PROFESSIONAL PROGRAMMING LANGUAGES IS DISCUSSED ALONG WITH THE IMPLICATIONS OF THESE FINDINGS FOR COMPUTER SCIENCE EDUCATION RESEARCHERS AND EDUCATORS, AS WELL AS FOR THE BROADER COMMUNITY OF RESEARCHERS STUDYING THE ROLE OF TECHNOLOGY IN EDUCATION.