Separate Start Unknown

Connie had some marbles. She gave 5 to Juan. Now she has 8 marbles left. How many marbles did Connie have to start with?

Direct Modeling:
Strategy: Trial and Error
?



Modeling:
Strategy: Join All
5+8=?






Counting:
Strategy: Count on From First
5 * * * * * * * *
6 > 7> 8> 9> 10> 11> 12> 13






Strategy: Count on From Larger



8 * * * * *
9> 10> 11> 12> 13





Facts:
Number Facts
? - 5=8
I know 5+5 ---10+3----13