Ten Diagnostic Assessments for 2.NBT.5: Are you looking for a way to see what your students know about adding and subtracting? Use these ten pages before teaching (to group your students), during lessons (to see who's able to apply their learning), and at the end (to find out who needs more help)!
Each diagnostic assessment asks the children to perform the following tasks (a sample problem is given for each):
• 2-digit + 2-digit without composing a ten: 43 + 25
• 2-digit + 2-digit with composing a ten: 55 + 28
• 2-digit – 1 digit without decomposing a ten: 68 – 6
• 2-digit – multiple of ten without decomposing a ten: 77 – 40
• 2-digit – 2-digit without decomposing a ten: 56 – 24
• 2-digit – 1-digit with decomposing a ten: 53 – 7
• 2-digit – 2-digit with decomposing a ten: 62 – 45
• multiple of ten – 2-digit with decomposing a ten: 50 – 18
If you have the resources, assess students individually and have each child explain how he/she did each problem (or have him/her complete the assessment as you watch, talking through his/her thinking).
Another approach: give two or three assessments during the course of a week, then analyze: which students have mastered which types of problems? Each problem requires a different depth of understanding: children who complete the first five easily but struggle with the last three, for example, need more instruction/practice with decomposing but may have mastered all the other skills. (The chart on the first page explains the math skill being assessed in each box.) A Teacher Record Chart is included so you can keep track of your students' progress.
So, for example, if you give your students three assessments and a child misses problem B on each assessment, you know that the child needs more instruction and/or practice adding 2-digit numbers with composing a ten. If another student uses manipulatives to quickly solve problem D, that student may be ready for a pictorial representation instead (drawing tens and ones, for example, and then crossing out the tens to subtract).
Be sure to give your students access to manipulatives (base ten blocks, number lines, etc.), because some students may still need concrete materials. Each box on the page is big enough for children to draw a picture if needed, or to write the problem and solve it using the regrouping (composing/decomposing) algorithm. You'll know your students are fluent when they don't need the manipulatives and they don't draw pictures anymore!
Happy teaching! :) Amanda
(2.NBT.5: Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.)