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By collecting stamps, that you get once you do complete one activity a day in Daily Training mode, you unlock more activities. You already are able to play Calculations x20, Calculations x100 and Reading Aloud activities as soon as you set up an account. Here is how many stamps you'll need to unlock each activity:

• 1 Stamp = Low To High
• 2 Stamps = Head Count
• 3 Stamps = Syllable Count
• 5 Stamps = Tips
• 7 Stamps = Stamp Designer
• 9 Stamps = Hard Head Count
• 11 Stamps = Hard Calculations x100
• 13 Stamps = Triangle Math
• 15 Stamps = Time Lapse
• 17 Stamps = Hard Triangle Math
• 20 Stamps = Voice Calculation