I added the amount as a hidden field and put the script in a form tag.
Here is the updated answer:
<form action="/charge" method="post">
<script src="https://checkout.stripe.com/v2/checkout.js" class="stripe-button"
data-key="<%= Rails.configuration.stripe[:publishable_key] %>"
data-description="Qsnag One Time Fee"
data-amount="<%=@amount*100%>"
data-email="<%=current_user.email%>">
</script>
<input type="hidden" name="amount" value="<%=@amount*100%>"/>
<input type="hidden" name="plan" value="<%=@plan%>"/>
</form>