Using the Bar Model Approach Singapore Math Using the Bar Model Approach

A couple of word problems… Easy to solve A man sold 230 balloons at a fun fair in the morning. He sold another 86 balloons in the evening. How many balloons did sell in all? Not-So-Easy to solve Lauren spent 20 percent of her money on a dress. She spend 2/5 of the remainder on a book. She had $72 left. How much money did she have at first?

In Singapore… Those two word problems would be solved using the same bar model technique. First encounter this technique in 3rd grade In 4th and 5th grade, technique applied to more difficult, multi-step problems By 6th grade, technique is being used to solve difficult problems

The Bar Modeling Technique… Teaches students how represent problems symbolically - algebraic reasoning Can be applied to many complex problems involving comparisons, part-whole calculations, ratios, proportions and rates of change Communicates what the learner already knows and shows them how to use that knowledge to solve the problem Sets students up to easily transition into Algebra

Part-whole model Daniel and Peter have 450 marbles. Daniel has 248 marbles. How many marbles does Peter have? 248 ? 450 Gives a visual model and helps student interpret language.

Comparison Model Daniel has 248 marbles. Peter has 202 marbles. Who has more marbles? How much more? 248 202 ? Compares two different quantities. Works for problems that are solved by subtraction.

Two Step Model Bracket is used to join the bars. Mary had 120 more beads than Jill. Jill had 68 beads. Step 1: How many beads did Mary have? Step 2: How many beads did the two girls have altogether? ? 68 120 Provides visual map to aid in thinking symbolically

Practice Problem Sam is driving to visit his sister. He drove 40% of the entire trip on Monday. Tuesday he drove 7/8 of the remainder of the trip. Sam has 60 miles left to drive on Wednesday before he arrives. How many miles is Sam’s trip.

Practice Problem Bob spent 40% of his allowance on books. He spends 1/3 of what's left on a shirt. He has $100 left. How much did he get for his allowance?