Shared by Win Elements
1.03 — Adding Signed Fractions and Decimals. 42 KB, eight figures, eight printed pages.
The angle. This skill could easily become “here’s how to find a common denominator,” which students already half-know and which misses the point. Instead the piece opens by insisting nothing has changed — same walk, same two instructions — and reframes the common denominator as the only new job: measuring how far the jump goes. Figure 2 makes that literal with two stacked number lines, halves over quarters, and a gold dashed line showing ½ and 2/4 are the same place. Renaming doesn’t move a number.
The analogy that carries it: you can’t add 3 feet and 1 yard without converting. The amounts are real, the units just don’t match yet.
The misconception figure. Your map says “handling the signs and the fractions as two separate problems and merging them wrong.” That’s a student who does ¾ + ½ = 5/4 flawlessly, remembers there was a minus, and writes −5/4. Figure 6 shows the wrong walk sending both pieces left — and the text names what got lost: the plus sign was an instruction about direction the whole time, not a label to attach at the end. The tell is visible in the picture: a rightward jump from the left side must bring you closer to zero, and the wrong landing is farther away.
The defense against it gets its own section before any computing happens. Figure 3 is two comparison bars — how far left I start (¾) versus how far right I jump (½) — concluding the answer is negative before a denominator is touched. Every worked example after that runs predict → compute → check against the prediction.
Figure 8 is the payoff. ½ − ¾ lands on −¼ — the same point as the opening example. Same walk, one looks like subtraction. That’s 1.04 already half-taught.
Use this in your own class
Copy the code, then in Sleedu: add a Page, click the <> source-code button in the editor, and paste it in.
