Practice Multiplying Decimals: A 6-Problem Mastery Check

Math with Mr. J

This video serves as an interactive "Mastery Check" for 5th-grade students learning to multiply decimals. Unlike a passive instructional lesson, this resource is designed as a practice session where students are presented with six problems ranging from basic single-digit decimal multiplication to complex multi-digit calculations involving decimals. The narrator, Mr. J, guides students to pause the video, solve the problems independently using paper and pencil, and then resume the video to check their work against his step-by-step explanations. The content focuses on the standard algorithm for multiplication, emphasizing the strategy of temporarily "removing" decimals to treat the factors as whole numbers, and then "placing" the decimal back into the final product based on the total count of decimal places in the factors. The problems progress in difficulty, starting with tenths multiplied by tenths and culminating in a three-digit by three-digit multiplication problem involving tenths and hundredths. Procedural fluency, including the correct use of placeholder zeros and column alignment, is demonstrated throughout. For educators, this video is an ideal tool for formative assessment or independent practice stations. It encourages self-regulated learning by allowing students to monitor their own understanding and receive immediate, specific feedback on their calculation methods. The visual breakdown of the solutions helps students identify exactly where they might have made an error—whether it was a basic multiplication fact mistake, a placeholder zero error, or a misconception regarding decimal placement.